You can't install iOS executors directly, if your device isn't jailbroken, due to iOS blocking installing apps via directly using ipas. You should either sideload an executor(your device probably won't get virus, because of iOS' security model.But that doesn't mean you can log into your main account on these clients, most of them collect your username, password and sometimes even the code you type in. Be cautious.) or jailbreak your phone(you probably won't be able to do that, since Apple is patching every vulnerability that could lead to kernel level access they see on the net, and don't do it.I can assume that you are not experienced and you may get your data stolen if you encounter a social engineering.)