Ruler - régua +4

Very convenient for making approximate measurements.
However, the placement of the “set point” in the lower right-hand screen is very awkward to use. I would highly recommend that you place the “set Point” where the camera button usually is, centered on the right-hand side of the screen, where it’ll be easy to touch with one’s thumb. This is especially true when using an iPad to make measurements.

I have been playing around with this and it's pretty handy actually since I don't usually need more than estimated distance nothing precise like hanging pictures etc but I got this because I was DYING to know how the watch app was adding to it....don't know yet. Still just shows a yellow screen with in/cm on one end and "Keep" on the other but the big 0.0 in the center does nothing.
If I am missing something I'd love to know I was really hoping you could at the bare minimum maybe see your measurements changing in that as you play finger-slinky trying to contort around to keep the phone str8, and at BEST able to lay your arm like on a door frame and move up and watch it tick off inches. I had a app on the phone that somehow did that using the GPS and gyro / motion coprocessor I think. Well if anybody knows the suspense is really not killing me

Gaining accuracy with this app does take a little practice, but I've measured 20+ feet with well under .5" of error. (The app gives you a way to unlock double the measuring distance.)

This is really for all those distances that would be hard to eyeball. (Is that 25" or 26"? Is that 7'6" or a bit more/less?) You probably aren't going to use it all that often, and it's certainly not the fastest way to measure ever invented, but it's easy and accurate and doesn't take any space in your pocket.