I'll tip my hand that I did work on devices that processed data without a computer. To remove the Smart part of the phone would mean a step back in time to find engineers that knew how to do this.
Given the astronomical cost of not using a Smart platform I doubt any company will invest the billions needed for a not smart phone that could do what you asked!
Maybe you are new to electronic design?
As to reliable GPS. I found one person wanting it to work inside buildings. Again, they didn't want to know how GPS works. Sad really.
Bob
I challenge Nokia or any other noble phone company that wants to hit a new demographic of people to make a basic/dumb phone that meets these standards:
-sexy, THIN, light, un-cumbersome, minimal design
-good camera (5mp+) and a front facing camera
-good music player with a sizable amount of storage for media
-reliable GPS
-good keyboard for texting (*not required if it does not work w/ design or if it is a touch screen device*)
For people who don't necessarily want to be connected to everything at all times and continuously distracted when out and about. but still practical as listening to music is important, taking photos is always nice, and a GPS probably being the most helpful/important connection for the device to have. That's all it needs to do, but it should do them WELL. Considering the phone market today, doing all this should not be too hard or pricey, and if done right would hit a demographic of people like me who despairs and rejects the constant technological stimulation based mindset of today, at least for the while I'm outside of my home experiencing life. I am one of the people that upon looking around a room full of people all engulfed into their smart phones not even acknowledging each others' presence, gets a feeling of existential angst and panic for the direction humanity is going in. I am one of those people that thinks technology should be more integrative and conducive to the ACTUAL human experience, and that we should strive to take a minimalist attitude when it comes to technology's presence in our lives.
I could also justify getting a tablet for myself more having a phone like this, as I could bring the tablet along whenever I feel on a particular situation I might need all the extra stuff. and that I'd rather be distracting myself with all the commodities of a tablet at home rather than at every possible moment. Also personally what deters me from getting a dumb phone is the cheap interface and feel as well as the god awful and archaic designs (pretty much because the phone market has given up on these). Image is a huge part of successfully creating this phone so a little money would have to be put into that as well.
In conclusion, I know something like this would be ideal for me and many others. So think about it.
The nokia 515 is the closest I've seen to something like this. Its pretty exciting.
PS do you think I could somehow relay this to phone manufacturers in a way that could have even the tiniest amount of influence?

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