I am also having this issue with the latest Sims Freeplay update.
I went to open the game today and it gave me the update in progress message. It was stuck on 95% and said I was running out of storage. I quickly moved to delete tons of apps and music from my phone, clearing out several GB of space...but the more space I cleared the bigger Sims Freeplay became. I watched the file size of the Sims Freeplay app on my phone grow from 2.9 GB to 5 GB. This is despite the fact that the download claimed that it was only 212MB or thereabouts. It was at this point that I read this post of another user's game size reaching 7 GB. I got discouraged. I agree that 7GB size for a game is unacceptable.
So, at that point, I decided to delete Sims FreePlay from my phone and just take the hit on the day's worth of play time that wasn't uploaded to the cloud yet. I hoped that I just had a corrupt download and that redownloading it would fix it. So, I redownloaded the app from the App Store, logged in with Game Center, and selected my saved game from the cloud. At that point, the game informed me that it needed to download additional content to load my saved game. That made sense to me, since I've been playing since right after the game was released and I have quite a bit unlocked inside the game. It told me the download would be 253 MB. No problem, since I have plenty of space free still. But then, for some reason, the download stalled at 151MB of 253MB. I tried restarting the download (by closing and reopening the app). The second time it got to 143MB. Then I tried again. The third time it got to 115MB. Each time it stopped, the app was telling me that my wifi connection was still downloading at somewhere between 4500kb/s and 5600kb/s.
So...because I love this game more than any other mobile game...I tried yet again. I closed every single app on my phone. I deleted Sims Freeplay yet again from my phone. I did a reboot of my iPhone. Then redownloaded Sims Freeplay, logged into Game Center, selected my saved game and again received the notice to download additional content. I tried to download the additional content. It got to 200MB of 253MB, further than I've ever gotten before. Then it stalled out again.
I just deleted the entire app again and am redownloaded it with 4.9 GB free on my phone. Prior to trying to sign in, it's taking up 304 MB. Now, if downloading the additional content and my saved game takes more than 4.6 GB, I may have to abandon this app that I've enjoyed so much. But nowhere in my downloading of content does it tell me that the app needs more than 4.6 GB, so I'm confused as to what is happening.
Let me say, I have been playing this game consistently since right after it came out. I have never had these issues downloading an update.
@ethilda Did you ever get yours working?
For anyone that has successfully downloaded the update on an iPhone, how much space is the Sims FreePlay app taking up on your phone?