Here's what I did to get wood grain on a cockpit floor for a 1/72 scale Pfalz DIII I was building.
I airbrushed with the floor with Model Master's enamel "Wood," and sprayed it with a clear coat. The clear coat was to protect the original color and make the "streaks" apply smoothly.
When the "Wood" and clear coat were dry (like the next day), I thinned some darker brown acrylic craft paint and streaked it on with a small paint brush until I achieved a sort of grain-look.
Since this particular project was a resounding failure and I scrapped it all, I didn't get as far as the wooden propeller, but the technique I used on the floor might work on a prop.
Good luck, anyway!
Don't know anything about smart phones though--the dumb ones give me enough trouble.