[Galaxy S II General] Azra2k:
First, I know there are tons of GPS tests, but all of them seem to focus on the extreme accuracy and less on the casual driving GPS experience. So I thought of making a small test and by doing this, I also discovered solutions to some existing unanswered questions. This is a subjective test, made by someone with some knowledge on the subject, but I am not an expert or anything close to that.

1. The test was made during an 800Km trip. 400km were done on the way "there" during the day and 400km on the way back in the evening. I used 2 GPS software packages: coPilot and iGo MyWay for Android. Both purchased. I also used 2 chargers, a cheap charger with 1x500mA and a more expensive one with 2x500mA USB ports. All the findings below were not influenced at all by the software used.

Now come the findings in a list:

a) Accuracy - I had absolutely no issues with accuracy. My position was fixed on the road even in dense urban areas with tall buildings. Initial fix took maybe 1 minute and there were 0 problems after that. Both coPilot and iGo performed really well, even at tight roundabouts.

b) Phone temperature while charging and using GPS - this is a bit more complicated to explain. First, I used a generic phone/PDA holder. For the first few KMs I drove with the phone held firmly in place. Outside temperature was 26-28 degrees and inside was 22 degrees. Clear skies with the sun shinning all day long.

Now, on my first few kilometers I encountered the all-to-common issue of overheating. My battery got to a temperature of about 54-56 degrees C and it would stop charging. The back of the phone was VERY hot all around the camera. So I started playing around to see how I can fix the issue and found a few "tricks":

- I tried to leave a small gap between the phone and the back of the holder (5mm). This lowered the temperature by A LOT! After doing this, the phone battery never went above 51 degrees.

-I then switched to Night Mode on the GPS software. This also lowered the temp by 2-3 degrees to around 48.

- After that I tried to place a piece of paper over it, protecting the phone from direct sunlight. Result, temperature never went above 46 degrees while charging.

- As another small note, I noticed that the battery gets hotter if it is fully charged or close to it. The difference was about 2 degrees between 90% charge and 50% charge.

Also, with the cheap charger I could not get the phone under 50 degrees, with the expensive charger I got at least 2 degrees lower on the temp display in similar conditions.

c) Loosing charge while charging - I used normal car USB chargers rated at 500mA per port. While the battery temperature was under 52 degrees, I never lost charge, it actually charged slowly (1% every 10 minutes or so). If the temperature goes above 52, I start to loose charge even though the phone still shows that it is charging. I think there is a self-protect mechanism that blocks the battery from charging when it is too hot.

Conclusions (after doing many combinations and seeing the difference in temperature): the phone is great for a GPS system if you follow a few pointers:

- Never cover the back of the phone. You should always have a small space there so the phone can cool itself. (very important, 3-5 degrees difference)

- try to protect the phone from direct sunlight... Being black it absorbs a lot of heat. (important, 4-5 degrees difference)

- use a good charger and not a cheap one. (important , 1-2 degrees difference)

- try to leave it on battery until your charge level reaches 50-60% and then plug it in. (less important , 1-2 degrees difference)

- use Night Mode, if possible (less important , 1-2 degrees difference)

On my way back, when the sun was down, I never got above 50 degrees no matter what I did.

Also, iGo seemed to use a lot more resources than coPilot. While on battery alone, I was loosing charge about 1.5 times faster.

* battery temperature was measured by "Battery Status" app. The readings were verified using the not-so-scientific method of touching the back side of the phone and "feeling" how hot it was :)