I want to buy an app real bad?

It cost a dollar & my mom thinks they're going to keep paying a dollar every month. &i told her that it won't but she said you never know i'm like it doesn't work like that. ( she doesn't know anythiing about apps or even how to use a iphone ) she said to ask my dad but i'm scared because he doesn't trust me with his card he thinks i'm going to keep getting other paid apps but i'm not. I just want this app and thats it! I'm so scared to ask him >.< ! Advice?

If its an apple product you can either get a voucher from the shop or get them to send your email a voucher I do that as my parents don't like me using their cards lol

Alright, he should put in the info with his card, then he can erase it and make sure its off your account, and you ARE right, apps only charge you once, and updates are free

GOOD LUCK!

also, you can get an apple gift card, and use that instead