A Confession App… with an imprimatur! CatholicVote.org
This seems like a very useful tool for those who already make use of the sacrament. It's a good diagnostic tool for our "operating system"--our wills, intellects, and passions/emotions. To what extent are these aligned with the mind and will of Christ, the Word made Flesh? Do we employ our passions in the service of intellect and will, or do our passions employ us? Who's the tool here?
If a smartphone application can assist us to grow in the knowledge and love of God, and in the proper estimation of self in light of God's knowledge and love of us, then by all means acquire it and use it!
There are dozens if not hundreds of reliable and exhaustive examinations of conscience out there in print and html form. It's like driving a Ford Focus vs. a Mazda Miata vs. a VW Passat vs. a Chevrolet Impala. Just use something that helps you move forward in your relationship with the Lord and your fellows, and maintain it.