AppZapp is the leading iOS Platform worldwide which is active in 13 languages and has over 3.5 million downloads. Per month AppZapp has 85 million Page Impressions and 150.000 daily users - which is quite awesome.
AndroidPIT is the biggest Android Platform worldwide which has 4.5 Million registered Users and already served 100 Million Installs. It is active all over Europe, Brazil & the US.
App Gratis is one of the biggest App Recommendation Platform which is active in 18 countries on iOS & Android.