Universal Searching for an app to visualize lines of position / bearing lines

[a.borque]

Hello!
I am looking for an app that shows a bearing line on a map when I take a bearing on a landmark with my iPhone.
My problem is:
when I walk along the coast, I can't tell apart the many small offshore islands. I just want to take a bearing on them with my iPhone, and then see a line on a map from my location in the direction of the bearing to see which island is intersected by that line.