Minutes to start and get the book open, and stuttering when doing things like choosing a book and turning pages was eventual my experience on all the devices: iPad Mini, Nexus 7, and a Samsung Tab 10.1. To be fair, someone else I know had an iPad Air for years and it was completely fine, so maybe they're the only tablets that actually work (or the Mini was a lemon and Androids just are bad?). Or maybe tablets are better since then: it's been a very long time since those devices went into a drawer, never to be used again.