Every iPhone developer has to deal with emails and reviews of this exact nature. The Apple apps/background processes eat tons of memory up over time and the ph

Every iPhone developer has to deal with emails and reviews of this exact nature. The Apple apps/background processes eat tons of memory up over time and the phone can get in a state where it has an absurdly small amount left to run apps. Restarting fixes this. Try restarting your phone, and if that doesn't fix it, then yeah, the app sucks.