I just bought a Nokia Lumia 800 and it has Windows Phone 7.8 installed on it. All good and nice but I'm not able to download any apps. When I go to http://www.windowsphone.com, select an app (even Facebook Messenger) and tap to get app details, a black window appears (as usual), but instead of the install button there's the following message:
This app is not compatible with your phone. This might be due to region, software need to be updated or app was created for a specific carrier.
My phone has the latest version of Windows Phone compatible with it, and the region is set to US (I've also tried many others).
Where can I download apps for this phone?