Providing you with general Catholic devotions and litanies compiled by Rev. Bonaventure Hammer, O.F.M.:

When you just wake up and about to begin the day, there are "Morning Prayers".

When you attend the mass (but it is not advisable to use iPhone during the mass), there are "Prayers at Holy Mass".

When you want to go for Confession and you want to prepare yourself better by praying, there are "Prayers before Confession".

When you are about to receive the Body and Blood of Christ (it is not advisable to use iPhone during the mass), there are "Prayers before Communion".

When you want to go for Adoration, there is prayer "Visit to Blessed Sacrament".

There are also other prayers included in this app:

Prayer to Our Suffering Redeemer
Prayer for All Things Necessary to Salvation
Litany of the Most Holy Name of Jesus
Litany of Loreto

With reminder feature, you can set daily reminder or location-based reminder to encourage yourself to pray more. For the location-based reminder, continued use of GPS running in the background can dramatically decrease battery life.

In the full version, you can find more prayers available:

When you are about to end the day, there are "Evening Prayers".
When you have finished attending a mass, there are "Prayers after Mass".
When you have received Sacrament of Reconciliation, there are "Prayers after Confession".
When you have received the Communion, there are also "Prayers after Communion".

Prayer to Sacred Heart of Jesus
Prayer to the Blessed Virgin Mary
Litany of the Sacred Heart of Jesus
Litany of All Saints

Please pray for holy souls in Purgatory and also for me as I continue to develop Catholic apps.