1. A method performed by a user device, the method comprising: downloading, by the user device, an autodialer application from an application server, the autodialer application permitting a user, of the user device, to purchase a prepaid calling plan and make telephone calls using the prepaid calling plan; receiving, by the user device and via the autodialer application, an instruction to purchase the prepaid calling plan; receiving, by the user device and from the user, payment information to establish a prepaid balance associated with the prepaid calling plan; presenting, on a display associated with the user device, confirmation information when the payment information is received, the confirmation information including the prepaid balance and access information; receiving, by the user device, a request to make a call using the prepaid calling plan, the request including a telephone number corresponding to a destination user device; calling, by the user device, the destination user device using the telephone number corresponding to the destination user device and the access information; determining, by the user device, a duration of the call to the destination user device; computing, by the user device, a cost of the call based on the duration of the call; and updating, by the user device, the prepaid balance based on the cost of the call.