Absolutely. I was in the first Android alpha test for OSRS and it's definitely come a long way from it's beginning. A lot of things are being made mobile friendly, and as long as they're careful with how much they allow mobile to affect the desktop version, it has a lot of potential to keep peoples interest. RS3 mobile is looking great as well, however it still has a lot of the game to be fleshed out to be mobile friendly, especially when it comes to UI.