We knew there were going to be a lot of Android-based devices on show at Mobile World Congress but what’s more interesting is the focus everyone has on the development and selling of apps.

One great example is emerging European handset manufacturer General Mobile.

One of the first to support Android in 2009 with its DSTI1 phone, it has a range of Marvell CPU-powered Android 2.0 handsets due in March and April; notably the Cosmos, Cosmos 2, Touchstone (all OS 2.0), and the OS 1.6 Brava.

More significant however is Storeoid, its own version of Android Market that will be enabled in all the 500,000 phones it expects to sell in 2010.

This is due to launch during April, and from the work in process screenshots has a much more polished feel than Google’s currrent storefront, even if the black background is perhaps a little off putting.

And what will be particularly interesting to see is how the combination of its mid-range devices (priced around 250 euros) sold into large, developing markets such as Turkey, Russia and other Eastern European states will create a sustainable ecosystem for developers, both local and international.