iPad: Apple App Store
Apple’s iTunes store isn’t just a repository for apps, as it’s also a supermarket for digital content, with music, films, TV programmes and books for sale. There’s also iTunes U, a source of free research materials on various topics, including many science courses. Lecture videos and course notes are usually free to download.
Before an iPad app can be sold on the iTunes store, it has to be verified by Apple, to ensure it conforms to strict design guidelines. These guidelines not only cover the appearance of the app but also its content, since there are restrictions on adult material.
Due to the massive popularity of not only the iPad but also other iOS devices (the iPhone and iPod touch), app developers are more likely to release iOS versions of their games and utilities before Android or for other platforms.
Currently, there are roughly 180,000 apps for the iPad (around 50,000 are iPad only). That's a lot of choice and, thanks to Apple's vetting process, few are poor quality.
Android: Google Play
The Android Market has recently been renamed to Google Play to reflect the wider range of content it now offers. So far, Google has taken a light-handed approach to moderating the apps that are for sale, with few guidelines that developers are forced to follow. Apps that are proven to be malicious are removed promptly.
Both Google and Apple's stores contain many apps that have a limited free version and a full (ad-free) paid-for version, especially for games. There are plenty of apps that are completely free though, including those for social networking sites, and others that integrate with, or replace, websites.
Prices can vary. Both Google Play and the App Store have regular sales, with many high-quality apps reduced to 69p or even less. Usually, they cost slightly more though, with some apps that have a lot of audio or video content, such as Brian Cox’s Wonders Of The Universe, priced at £4.99. The average price of apps is around £2, but Apple's premium apps such as Pages, Keynote and Numbers, cost £6.99 each. Some apps, especially satnav programs, can cost upwards of £40.
BlackBerry App World
Blackberry's App World has fewer apps than Apple and Google's stores, but a good proportion of these are of a high quality. The PlayBook received a content boost after RIM added limited Android compatibility to it, but RIM subsequently did a U-turn and has now decided that it will probably remove support for 'sideloading' Android apps to avoid the "cesspool of chaos" in the Google Play store. RIM is currently working on a new way for Android developers to repackage their app for the PlayBook so they can submit it to RIM for testing before it goes on sale.
There are fewer free apps available in the App World and prices are slightly higher than in Apple's store: expect to pay around £4 for apps that aren't free.
It doesn't take much to work out that Apple's App Store is the clear winner of the battle here. There's a broader choice and almost 40 percent of apps are free. Add to this the fact that there's also a massive library of music, films and TV shows available to download from iTunes and - for now at least - the iPad is the obvious choice if you'll be installing a lot of apps.
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