Board Thread:Questions and Answers/@comment-24979583-20140802052452/@comment-10412586-20140802083316

The iPad/iPhone needs at least 500MBs(1/2GB) of free memory to power the RAM to run smoothly.

If the iPad says that there is not enough memory left. You must consider deleting some data to be able to download SG. Try deleting some games that you don't want.

Once I "forced" multiple games to download at once and my memory was only left with 600+MB. After I download both of the games, my iPad was left with 0MBs. A lot of stuff changed in my iPad, some of the saves from my other games were deleted to create free space. So it's important to keep at least 500MB available on your device or you would lose important data.