It's no small feat to get a fully 3D space sim with custom craft building and realistic orbital mechanics to work well on a device that fits in your pocket, but we've about got this licked.
At this point, we are hoping to release in September. Since that's right around the corner we went ahead and set up the store pages and you can show your support by pre-ordering on the iOS App Store or Google Play!
Technical Note:
We are still continuing to improve performance on mobile, but as of right now you will need a device with at least 2GB of RAM. For iOS users, this means you will need at least an iPhone 6s or 6s Plus. It's possible that we might figure out how to get it working well on older devices, but we cannot guarantee it. The good news is that PC and Mac players should expect a bit of performance boost as well from all the work we're doing to get SR2 ready for mobile.