Dr Tim King, CTO of 5app, offers some advice on how to keep app spending sensible.
Many chief execs and CIOs are shocked at the full cost of developing mobile business apps.
It's better to understand in advance and take steps to manage the costs, so here Dr Tim King, chief technology officer of app toolkit vendor 5app (a finalist in the ME Awards 2012) offers some advice on the subject:
Most would agree that the mobile app design process takes a considerable amount of time – perhaps two weeks solid work for a single target device, or more if the app is complex and has many different user interface screens.
The designer also needs to understand the expected user experience for the phone in question, so if you are looking at a cross-platform app, then the designer will need to have used the specific phone model at some point to better understand the end user experience.
In addition, if you want to include BlackBerry then you need to understand how the touch screen models work and compare them to the joystick controlled models - adding another week of development time for each simple, cross-platform app, and potentially more for complex versions.
Here there are more hard facts. Twitterific took 1500 hours to create according to one of the developers, which at current US rates is $150,000 (£95,000). The developer of the fairly simple official Barack Obama app says it took 25 weeks but could be done in half that if he had to do it again so that would be $50,000 or £32,000.
Apps can easily be split into a few categories:
- A simple app, with all the data stored on the phone and no interaction with any server, might take between two and four weeks to develop.
- On the next level, apps that extract data from a database and display it in a simple list can be expected to take double that time.
- For more complex server-side integration with data being cached so it works offline, the estimated time this would take is around eight to 12 weeks.
- A full-scale enterprise automation app, with integration to business processes and possibly including a shopping cart and payment gateway, will take anything from three to six months.
These estimates are for a single target device, i.e. Android phone or iPhone but not both. Although the back-end integration will be shareable, none of the code will be unless you use a hybrid approach and create most of the user interaction within a browser instance.
This is an attractive approach when considering cross-platform apps otherwise the cost doubles or triples depending on the extra devices that need to be supported.
Making sure the app doesn’t crash when in use requires extensive testing, so a simple app is considerably quicker to QA than one that interacts with back-end servers. When developers conduct tests to ensure they have a reliable enterprise automation app, they have to cover all scenarios where the phone has mobile data signal and then it drops, or it switches to wi-fi.
These data carrier transitions are tricky to handle, as the IP address of the device changes and thus the normal error correction offered by low level protocols, such as TCP/IP, isn’t useful. Additionally, a new IP address normally requires a new authentication step to be gone through.
Then there are the different versions of each mobile platform that need to be considered. If enterprises are going to support the original iPhone and iPhone 3G, then they run iOS 3.1.3 and 4.2.1 respectively. For Android, an enterprise will need to test at least 2.2, 2.3, 3.x, 4.0 and 4.1 as there are significant changes between them.
If a business wants to develop for BlackBerry, then they will need to test releases 5, 6 and 7 as devices with these versions are still being sold. That’s not to mention upcoming Blackberry 10 and Windows 8.
In all cases, the testing phase will start at 10% of the development time and will be that again for each OS version needing to be supported.
The below table provides some comparison for costs. In each case, it is assumed the median estimate for the development phase and an hourly rate of £35 for design test and a daily rate of £300 for developers. Testing is 10% of the cost multiplied by five, eight and 11 for each of the operating systems.
I have allowed for some savings when considering cross-platform apps due to the re-use of the back-end code, saving one, two and three weeks respectively as the apps get more complex.
These estimates are just that, of course, and real costs may end up more than double the above, especially if the project is poorly managed and/or the scope of the app has not been tied down.
But it’s safe to assume that using traditional development techniques to create a simple single-platform app will cost around £10K and a cross-platform enterprise app won’t come in under £100K.