For the last several years my carry flashlight is a Streamlight Microstream clipped in my right front pocket, every day.
Fenix E12, runs on a single AA battery and is always in left front pocket.
E12 Fenix Flashlight - Fenix Lighting
Fenix E01 single AAA battery on my keyring.
Works for me. It's a handy little light.
The current wisdom that cell phone replace flashlights l feel is misguided. It is fine for picking up dropped keys in the parking lot ten minutes from home but most of us can find ourselves off the grid from time to time, or at least out on the edge of it.
In a true nighttime roadside emergency measures that shorten the life of your communication device should be avoided.