IPhone 4s network booster app where do I get it are their any similar apps?

[J.W1GGY]

I have the IPhone 4s and I'm using the sprint network which doesn't get a very good signal into my building. I know of the 3G network booster app and here it works only I can't find a site that my phone which is not jail broken will let me download the app. Does anyone know where or some good sites to get the 3G network booster ipa? another question I have is does the app store have a similar app more up to date that's truly legit? I downloaded a free memory app and booster app and was ripped off by both. Please respond ASAP if you have any info in regards to what I've mentioned.
Thanks New Member
J.W1GGY 👀