04 May

Xamarin Cross Platform Application Development – Book Review

Xamarin Cross Platform Application Development – Book Review

Andy Flisher is a Software Developer based in the North East of England specialising in cross platform development. Mobile Development experience includes Windows Phone, Android, and iPhone Apps. Desktop Software Development includes bespoke Windows, Linux, and Mac Applications. Web Development Skills include PHP, Perl, Python, Xamarin, C#, ASP (Classic and .NET). Andy also has some Industrial / PLC Programming experience – Andy Flisher on Google+

This is a review of the recently published book “Xamarin Cross Platform Application Development” by Jonathan Peppers.

This book is openly marketed at existing, experienced C# developers so it’s certainly not for beginners, and whilst I don’t fall into this category the nature of projects I work in require mostly ‘linear’ development (Web, PHP, Perl, Python, VB etc over the years) so concepts like MVC, MVVM and in particular IOC (Inversion of Control) are newer and less clear. Thankfully this book has resolved that through it’s excellent practical examples.

One area this book doesn’t touch on hugely is the level of planning required for MVC applications, you can’t just ‘jump in and code’, but that’s potentially a book in itself, but what the book does very well for me, is explain the View, ViewModel, Model and Controller concepts in terms of the classes and data layers required. The book also introduces Interfaces (something I always saw as an unnecessary layer of complexity) which I now ‘get’ in terms of flexibility, and in particular to give the developer options in a cross platform environment.

The icing on the cake is ‘Inversion of Control’, whilst the book doesn’t particularly explain this convention in huge detail, I think it is actually to it’s credit, any more and the reader will be bogged down in unnecessary detail and complexity. It basically gives us the service layer that ‘glues’ the application together, allowing use to create and register our ViewModels as Services and thus make them available to use throughout the app with a single line of code. I’m sure that my description is not hugely more constructive than the words in the book themselves, but the working example of the XamChat application completes it.

Which is my main point, am sure many people work differently, but for me working examples of code are what makes it stick in my mind, it helps it all make sense. Throughout this book you will be building bit buy bit a working chat application, firstly in Xamarin.iOS (but using the all important cross platform and code sharing concepts learnt at the beginning of the book), and then re-implementing the same application logic in Xamarin.Android. The nice touch, which some may see as lazy, was that with the Android example you are taken to a certain point and then left to finish off using the examples you already have. A real, and practical exercise which I think will do the reader good. It wouldn’t be a huge leap further to recreate in Windows Phone, for the ultimate practical extension.

The Xamchat application is then extended through the Windows Azure platform to use their backend for data storage (a good example of how the same Interface can be re-used to store on different platforms), and to implement cross platform push notifications.

Lastly there are chapters on using Xamarin Components (including Xamarin.Mobile for Contacts, Camera and Location functionality), and actual App Store submission and their different processes, processes that even the most experienced developer can struggle with (Apple Certificates and Profile expiry anyone!).

In summary, this is an excellent book for any would be cross platform mobile application developer, yes you need a good understanding of C#, MVC and similar concepts, and the individual mobile platforms and general development processes themselves, and those things don’t come over night, but this book binds it all together with real world examples, working code (a novelty for some books) and actual code and methods you can take away and use in the real world.

Buy it, read it, and take as much as you can from it – “Xamarin Cross Platform Application Development” by Jonathan Peppers

10 Apr

Baby Biography Mobile App – Project

Baby Biography Mobile App – Projects

Andy Flisher is a Software Developer based in the North East of England specialising in cross platform development. Mobile Development experience includes Windows Phone, Android, and iPhone Apps. Desktop Software Development includes bespoke Windows, Linux, and Mac Applications. Web Development Skills include PHP, Perl, Python, Xamarin, C#, ASP (Classic and .NET) – Andy Flisher on Google+

The mobile app will be developed using dotUK’s cross platform, and multi platform mobile app development skills. This skill set is a niche, and dotUK are one of the few development companies, certainly amongst North East Mobile App Developer’s to offer true, native mobile apps that can be developed simultaneously across the core mobile application platforms, in parallel.

Baby Bio Mobile App

The Baby Biography mobile app will be offered initially as an iPhone app, and also as and Android App, in addition to creating Baby Biographies within the app, other features include;

  • Creation of Multiple Books
  • Sharing of Baby Moments and Photos ‘In App’ to Social Media
  • Free Cloud based storage of all your books and moments
  • Collaboration with other parents
  • Conception and Pregnancy calculators
  • In App Support

Cloud storage and collaboration will be offered through dotUK’s in house cloud storage framework which allows the app to seamlessly synchronise the baby biographies into the cloud in the background when connected to a suitable internet connection, but doesn’t in any way impeded or restrict any app functionality when working offline.

Originally posted at http://www.dotuk.net/news/home-page-news/baby-biography-android-iphone-mobile-app-project/

19 Feb

You get what you pay for – Mobile App Security

Mobile App Security

You get what you pay for – App Security

Andy Flisher is a Software Developer based in the North East of England specialising in cross platform development. Mobile Development experience includes Windows Phone, Android, and iPhone Apps. Desktop Software Development includes bespoke Windows, Linux, and Mac Applications. Web Development Skills include PHP, Perl, Python, Xamarin, C#, ASP (Classic and .NET) – Andy Flisher on Google+

In the course of work this week I had a cause to audit an iOS App that a prospect had had developed by a local competitor here in the North East, the reasoning for this was that the prospective client was looking at moving the hosted back end (ASP .Net, SQL Server – standard stuff) and wanted a price.

Mobile App Security
The purpose of the audit was to check what network connections the app was making, and correlating with what I knew about the backend hosting, just to make sure there were no surprises, we didn’t have the source code for either end yet, it was just a pricing exercise at this point (As it happens the App is written using PhoneGap so we *did* have the source code, but my route was quicker).

So, I installed the app, redirected my iPhone through a proxy server, and fired up the app – and proceeded to stare in horror. The app instantly, on first run fired up an un-encrypted, un-authenticated connection to the backend host and promptly downloaded the usernames, password, emails, and more for *every* user in the system. It then keeps a copy of these locally, and uses those details to authenticate later.

Why is this bad, in laymans terms, because anyone, on the internet, who knew the url the app uses could download the same list. Would people be interested in logging in to this system? Probably not, do people use the same username and password for Amazon, Tesco, Online Banking – absolutely, and there’s the problem.

Solutions, well it’s about paranoia, but key areas;

  • Authentication – Implement simple basic authentication so that the app logs in to the webservice it pulls the data from.
  • Https – Implement and SSL connection, then at least all traffic too and fro is encrypted (important as Basic Authentication is over plain text, so without https it’s still sniffable)
  • Change the login mechanism to completely remove the need to download all user info at all.

What’s really frustrating though, and actually makes the ‘You get what you pay for’ title of this post a misnomer, is this wasn’t a cheap solution.  The client paid a very reasonable amount for this app and solution.  This is the sort of thing we see, and sadly expect, when a ‘cheap’ solution is offered as a counter to ours.  We’re not expensive, but not cheap, we do do things correctly though.  It’s a classic case of the customer not knowing what they’re not getting, they trust, and assume that a professional job is being done, without really asking too many questions about why it’s cheap.

In this case no excuses though, I’ll not name anyone, and we’ve raised the issue with the client – We certainly won’t be taking on the hosting until it’s resolved!

Andy works for dotUK (www.dotuk.net) a North East Based Web and Software Development firm he helped found.

04 Mar

H Jarvis – Support Software Case Study – dotUK

Originally From H Jarvis – Support Software Case Study – dotUK

Andy Flisher is a Software Developer based in the North East of England specialising in cross platform development. Mobile Development experience includes Windows Phone, Android, and iPhone Apps. Desktop Software Development includes bespoke Windows, Linux, and Mac Applications. Web Development Skills include PHP, Perl, Python, ASP (Classic and .NET) – Andy Flisher on Google+

H Jarvis, a North East and Marske based Quality Windows and Doors manufacturer head a need to improve upon existing quality control and customer support processes, increase efficiencies in service engineer response, and to allow end users to self service their own support cases

  • Client H Jarvis – North East based window fabricator
  • Platforms Web, Web Services, Outlook Calendar Sync
  • Technologies PHP, CSS, JQuery, Javascript, MySQL, REST API, iCal / Webcal, JSON

H Jarvis are a multi site company with bases of operation in Marske (North East England) and Blantyre (Scotland), and had an existing interconnected IT infrastructure linking the two sites. With that in mind it made sense to build a Web Based Software Solution, in this case utilising dotUK’s own bespoke web services framework.
his framework, built for purpose, is built upon a PHP, MySQL REST based API framework that allows seamless, consistent, and secure data exchange from the hosted API hub and the end client’s browser. Again utilising PHP and JQuery in the web client we were able to offer an improved experience to the end user, without the traditional stop, start, or click and wait frustrations of traditional web software.

H Jarvis – Support Software Case Study - dotUK

Functionality wise have built a central support system for all sites which registers and manages all currently active customer support cases, with SLA support and comprehensive management reporting. In addition to case reporting the system also offers manufacturing build orders for remedial work and iCal calendar synchronisation with Outlook.
Fitter appointments are booked by the agents on an informed intelligence basis to minimise unwanted travel time by allocating cases to geographic zones and forward looking appointments to ensure that fitters are booked in when next in the appropriate locale. This appointment picking process also includes real time estimates of travel time so the most informed appointment booking decision can be made.

End use wise the system also includes a web based portal for key clients to view and manage their support cases, including any updates, notes or case changes. This allows end users real time access to updates when they need it, yet at the same time freeing Agent staff from fielding update enquires directly .
The solution is built upon dotUK’s managed web services platform hosted in the North East which allows for scalable database clustering, high availability, and includes 24/7 monitoring and management, and full data backups to an offsite datacentre

08 Sep

The iPhone App for Zenoss – That’d be KyK

The iPhone App for Zenoss – That’d be KyK then

Andy Flisher is a Software Developer based in the North East of England specialising in cross platform development. Mobile Development experience includes Windows Phone, Android, and iPhone Apps. Desktop Software Development includes bespoke Windows, Linux, and Mac Applications. Web Development Skills include PHP, Perl, Python, ASP (Classic and .NET) – Andy Flisher on Google+

Kyk - The iPhone App for Zenoss

Kyk - The iPhone App for Zenoss

Zenoss is a monitoring system, we use it the office, and basically it sits on one of our servers out in the Cloud (the Internet to most people) and regularly monitors our kit, servers, and our clients kit too, to make sure they’re still up and doing what they should. If something disappears, a disk gets full, or a server overloaded it alerts our Engineering team and we swoop into action. When there’s an alert it keeps on alerting until you respond and acknowledge it – that’s where KyK comes in.

KyK?- It’s from the Afrikaans for ‘Watching’ – which is the easiest way to explain what Zenoss does.

Yes, yes, very clever – but what is it? Well, it’s an iPhone App, an iPhone client for Zenoss if you will, although not just iPhone, it will work on any handheld iOS device, so that’s the iPod Touch and the iPad – Oh, and I wrote it, I’m an App Developer too you know, so that’s Web Based Software, Desktop Software, and Mobile Software – clever me :-)

Back to the top, when there’s an alert in Zenoss you have to get on line, login, see the agent and acknowledge it. Alerts don’t happen at convenient times, so KyK is aimed at making it easier. Fire up the App, it automatically polls your Zenoss server and lists any events. New events are highlighted at the top, tap, confirm, acknowledged – that simple, convenient, mobile. You can also view more detail and alert history for events too if you want.

What’s next? Well KyK (and KyK Lite – a free version that lets you see events but not acknowledge them) is out there now in the Apple iOS App Store, there’s a version for Android in Beta (that basically means half done and in testing) and it may expand beyond that, I have half an idea for an enhanced iPad / Tablet version with a lot more management features, but we’ll have to canvas demand to justify developing that.

How’s KyK doing, setting the Zenoss Community on fire? Not yet, but it’s only been out for a few weeks, we have customers in Mexico, Canada, the US, South Africa, and of course the UK – it’s interesting being global – but also a challenge. I deliberately wrote a support / feedback mechanism into the app so users can contact us as easily as possible, it’ll also send me useful debug logs so I can understand what has and hasn’t happened, so that makes life easier, but of course we have timezones and languages to deal with, thankfully most people internationally speak better English than we do. Today I’ve released version 1.1 which fixes a couple of minor bugs and user interface anomalies, and massively adds support for Zenoss 4 and above (Annoyingly Zenoss 4 came out of Beta whilst KyK was in the worlds longest App Review, so we had no opportunity to test and ensure compatibility before release), and have a few features to add for the next release. The big milestone will be 1.2 when it’ll go live for Android too, just need a Tardis and a few round-too-it’s and we’ll be there.

Bigger plans, commercially, we’d like to talk to Zenoss themselves, or their clients, KyK is written in such a way that it could easily be re-branded, or custom re-written as an Enterprise App to be deployed large scale – but that sounds a lot like Marketing, which is for another day and the right frame of mind, step 1 (and 1.1) complete.

In the meantime if you use Zenoss, or know someone that does, and have an iPhone in your hands, buy KyK for Zenoss on the iPhone, leave a nice review (if you can), and make me smile, thus justifying a lot of long hours and thought!
Available on the App Store

Andy works for dotUK (www.dotuk.net) a North Based Web and Software Development firm he helped found.

© Andy Flisher (Where Permissible)