Q. What should I do if I deposit a check using my smartphone, and it doesn't get properly credited to my balance?

A. Most mobile apps provided by banks now offer a very useful feature: You can deposit a check simply by taking a photo of it (the front and the back) and submitting it through the app. While bank apps make it quicker than ever to deposit a check, the funds won't be credited to your account immediately. Most banks make the funds from "remote deposit capture," as banks refer to this transaction, available in one to two days, according to a 2014 Pew Charitable Trusts study of 100 banks and prepaid card issuers.

If you are using mobile check deposit to deposit a check to a prepaid card, which you may be using as a substitute for a checking account, the funds can be available immediately–for an added fee, according to Pew. But even here, there can be delays. The American Express Bluebird prepaid card, for instance, won't credit a mobile check deposit to your account until six business days after you make the deposit.

If your mobile check deposit never makes it to your account, one reason could be a glitch with your phone. When you took the picture of your check, it's possible that the phone didn't capture the photo because of insufficient memory problems.

Another reason could be that you reached the monthly mobile check deposit limit set by your financial institution. Banks, credit unions, and prepaid cards set limits on the total amount you can deposit by mobile app to help prevent against fraud. The limits can be as low as $1,500 per month.

If you find that a deposit did not go through, don't try to re-deposit the check by smartphone unless you've received a message specifically indicating that the transaction was not accepted. Be sure to hold onto your check until you're certain the funds have been credited to your account. You can also call the customer service number of your bank or credit union to find out what went wrong and follow instructions about how to rectify the problem.