Hello.
Been lurking here for a while... & decided to join up so I could throw my $.02 in...
I've been using data loggers for about 4-5 years now. And I admit, once I found something that worked for me.. I mostly stopped looking..
First off.. I'll assume you have discounted using your smartphone for whatever reason as a data logger.. Don't have one.. poor GPS reception, battery life.. mysterious program crashes.. etc. All are vaid & reasonable reasons.
The data logger that I really like is the Holux M-241
Holux Technology, Inc. | Product
It's just the right size ( a little bigger than a old style roll of 35mm film ). I just use the lanyard to tie it off to the outside of my backpack.
Runs 10-12 hours on 1 AA battery ( can be powered by USB )
Good GPS reception ( good enough to work though an airplane window from 1-2 seats away )
Plenty of memory. It will store 130,000 datapoints. If you run it 1 point per second that gets you about a day and a half.. But that is serious overklll. You can have it log by time.. Every 1, 5, 10 etc etc seconds.. Or, by distance traveled 50 feet & up. Using the log by distance setting you can have good track accuracy & the memory can last a week to weeks..
Has a LCD screen & backlight to tell you what it is doing.. Where you are, your speed, direction. Though, I have mostly used it for hiking/City walking.. The screen is probably too small to read & get useful info as you go.. But at least you will know it is on.. and tracking.
It's not too expensive.. About $70 (USD ) from ebay.
Only one downside.. There is a weakness in the electrical contact on the battery door. I had the clip come off on my first one.. On my 2nd one I put a small dab of epoxy on the 2 spots where the clip is 'welded' to the battery door.. No problems in the past 3 years..