I understand not wanting to charge $0.99 to a credit card. Through Google you can bill to your Sprint account, but Apple you will not be able to. Below I have provided the steps for Google play.
http://support.sprint.com/support/article/Pay_for_a_Google_Play_application_on_your_monthly_Sprint_bill/case-wh164052-20110418-114136?question_box=Make a Google Play Store Purchase&id16=Make a Google Play Store Purchase
I hope I was able to answer your question, and if you need anything else please let me know!
Sprint Social Care Team
Tuesday –Saturday 1-10pm mst.
I am trying to do the same thing, pay for googleapps on sprint account. I follow the instructions and get an error "your purchase on your Sprint USA billing account was declined". I have three phones on my plan all with different gmail addresses. The phone I am trying to download to is not the primary. Is that the problems and any suggestions to help. I looked for a setting on my Sprint online account to authorize to all 3 phones but did not see anything like tat.
Make sure you are not authenticating via the wireless and only the phone network. I found it has issues and when I shut off wireless and only allowed Sprint network to connect it worked. NOTE if you have an air rave you may still need to get away from it I have one and I needed to stay clear of it before it started to work.
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