This is going to be valuable information for Catholic readers who should know that Vatican is against confessions by iPhone.

The view was expressed that without in-church confessional there is no personal dialogue between the confessor and penitents and the mobile app will not be able to make it.  
To make the case more understandable, the same thought was repeated in clear terms by the Federico Lombargi, Holy See press officer. He said that no ambiguity must be in this question and it is impossible to confess by iPhone and is allowed under no circumstances.

These words automatically invalidate the permission given by Kevin Rhodes, the Catholic bishop, who blessed the idea a bit earlier. Moreover the app was developed by the company Little App, which collaborated with Catholic Priests to make the Confession.

The description of application given on the iTunes by no means asserts that a Roman Catholic App is a replacement but rather a useful tool. And it should not be used instead of church going, but the statement of Vatican is expected.