Sleep Cycle - Bio-alarm clock that wakes you up at optimal times based on your sleep patterns.

Headspace - Meditation made simple. Brilliant things happen in calm minds.

Sleep as Android - Common alarm clocks ignore your sleep cycles, they wake you on schedule no matter your are currently in your deep sleep. Waking up from deep sleep is unpleasant, it makes you tired and it may negatively affect your productivity during the whole day.

Nao. - A social platform to encourage mental well-being

Talalarmo - Minimalistic android alarm

Calm - Calm.com can help you reduce stress and increase calm.