1. Imam Ja’far as-Sadiq (a.s.) has said that the person who recites this surah in his recommended prayers will have a shining face on the Day of Judgement.
2. The one who recites this surah will be patient in adversity and will be counted from among the people of truth.
3. If this surah is written after ‘Isha prayers and kept, it will be a safety from the tyrant ruler in whose presence one is brought.
Surah Al Asr is best for increasing love and harmony between two people (husband and wife and any other mahram relation). (Please don't use it for purposes outside the boundaries of Islam, like love affairs as these things have no permission in Islam).
* Surah Al Asr increases patience and steadfastness.