Please help? wifi without a data plan htc evo 4g

[StevenD88]

ok so heres the background. i just bought the new gs3. Prior to this i had the htc evo 4g. my favorite app was adownloader which enables you to dl torrents but kills your battery especially if you dl seasons of shows. Now heres my problem i dont want to use the app on my gs3 because i dont want to kill the battery but when i put my now deactivated evo on wifi it holds the signal for about 10 mins and then im unable to use it anymore unless i restart my phone and turn on wifi again. the wifi itself doesnt seem to be a problem. Please help me someone :'(