Usability 
After experiencing a lot of frustration with Java ME download sites, I created BoostApps, a free mobile Java app store for non-smartphones.
BoostApps is a desktop and mobile web download site that doesn't try to second guess the user. Unlike most other download sites, it lets you download both jad and jar files using any browser on any phone or with a PC for side loading. All the downloads are freeware or ad-supported and include essentials like Opera Mini, Gmail and Google Maps. There are also a lots of games and all sorts of useful apps including instant messengers, browsers, email clients, clocks, file managers, eBook readers and calculators.
Downloads are organized into categories and both the mobile and desktop versions of site have a powerful and easy to use Google powered site search built in.
All games anmd apps on BoostApps are tested and checked for malware. App listings include whether the app is freeware or ad-supported, how big it is and whether it uses potentially costly data. There's a link to the original author or publisher's website if one exists.