Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Does this product (and its magnet) screw up the GPS? I have iPhone 5s and heavily use Google map to go places. Thanks.
Document: First purchased this product from my local hardware store for myself. Directions are clear about how to mount properly. All products for the mounting are proved. It has stayed securely adhered to my iPhone case and the car dashboard (over three months). The phone stays securely attached to the magnet even over bumps (or curbs :/)  Its great to use when using your GPS on your phone. And for me,  having a place to put my phone while in the car.
I have this item! I used it to go on vacation to use GPS on my phone and it was perfect.
I didn't put anything together until after I used a Screen Write to take a screenshot and to start drawing all over my screen and noticed that only a center circular area around where the magnet was attached on the other side was affected. I haven't had any problems with the GPS using Google Maps.I really like the product but I think I'm going to have to give it to my wife. I, like one of the other reviewers here, bought the Note 3 specifically because of the S-Pen.
The phone attachment fell off my case in my pocket in about 10 minutes. The goop an the dash on my car was nasty and did give me some concern. However, use GooGone to remove it and it came off like new eventually.This is an awful product. Sticky goo that does not hold well to a multitude of different phone situations make it a fail. The magnet possible GPS compass disruption never happened but only because I never got to use it for any extended period of time.
This is a really interesting product. The magnets work well and adhere to each with a solid feel. The GPS I connected to it has an antenna in the back middle section that flips up so I could not attach the female receiver in the direct center as the instructions called for. The result is that the GPS turns to the left or right when I go around a corner. I am not certain this wouldn't happen even I had centered it but I don't have a way to find out.
I really liked the design and functionality, however, the magnets have damaged my GPS in my iPhone. I use it almost daily in my car as I am a real estate broker. Location is now often 500 feet away and sometimes up to 1500 feet. I took my iPhone to apple store and they reset the modem. It still will no longer effectively track the location. There should be a big warning.
I purchased a Steelie from Nite Ize when I first found out about them in early 2013 to use in my company car. I am on the phone a lot while driving and thought this would be a good alternative to buying another windshield suction cup cradle for my iPhone. The car has bluetooth but this thing worked great to easily see who was calling, make calls and to use my phones GPS.
What a great product! Unobtrusive and sturdy on the dashboard with a positive 'click' when attached. Granted, not everyone will want their device to have the magnet on it, but if you use a case you can easily change that to one with or without the Steelie magnet. However, having a fast, secure attachment point for using hands-off phone or GPS is worth it to me. And since there's no post extension there is very little movement due to vibration.
I saw this product as a kickstarter and immediately was intrigued. I have been looking for a minimal solution to mounting my phone in my car for as long as I can remember. Little did I know it would be just as valuable to me outside of my car as well. I had it originally on my iPhone 4s directly mounted to the back of the phone, and now it is on my 5s mounted on a rubberized case. Both have worked flawlessly and never failed on me.
I originally bought this with the idea that I could mount an car holder that would then hold the iPhone itself. It's apparent the friction of the magnet on the ball is barely enough to properly hold just my iPhone. Since I don't like the idea of attaching a magnetic disc to the back of my phone, I won't be doing that. However, if I ever want to mount something small, I'll go right to the Steelie mount.I also accidentally put a gash in my dashboard when I removed the Steelie.
Answer: Since I attached the magnet the compass still works OK but the directional arrow on google maps rotates randomly, makes it very difficult to know which way your traveling. After I removed the magnet the phone still acts the same way.I can't be sure if the magnet  was the cause but its pretty broken now and it may be as its quite an old iPhone 4S or that the magnet permanently damaged it, hope this helps.