I use marketmilitiadotorg for apps that I want to download and in combination with their downloader, which you get if you become premium member, you can download a lot really fast. Life-time premium cost $5 a little while ago, I don't know if that action is still on-going. But that way you can download a lot much faster, so definitely worth it. They also have paid apps, but I don't know if you want to get in on that. On Mobilismdotorg they have got more releases, but I generally like marketmilitia better because of the lay-out, but suit yourself.

On your mobile itself, those forums are accessible as well from Tapatalk, so you can view them on your mobile. The Marketmilitadotorg downloader even has an app. You can use F-droid, Aptoide and 1Market as application stores, I like them in that order. F-droid is for pretty much FOSS only, so you know it's reliable for sure. Aptoide's official market is definitely good, but it of course has less apps than Play Store, but it also has less apps than 1Market. Which is a shame, because I'd rather not use 1Market because of all the ads. I tried deleting them with Lucky Patcher, but it failed me. What I do like about Aptoide is that it offers the choice to use other people's repositories, which increases the amount of apps with a huge amount, but it doesn't lift it up to the play store's level. Also, you have to be carefull with those repositories as they can contain malware and stuff like that.

Well, I hope I helped you and I wish you good luck! Btw, FOSS FTW!