I would argue that point! I've used a mates Garmin and in my view the app I use on my iPhone shits all over it.
It's faster, clearer and has many more options but you don't have to use these either if you're techtarded. I've also never not been able to get a signal, and from some things I've read people can get signals on their phones where they struggle with dedicated GPS'.
As for battery life I bought a portable juice pack that can charge the phone from 0 to 100% about 5 times, as well as be used to recharge my torch or head lamp or anything else USB. One of these plus a phone is still smaller than a GPS.
For durability buy a shock proof, water proof, dust proof case.
But we've been over all this in the other thread the original poster mentioned, so I will pipe down now haha.
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