I mean--"programmable feature phone with smartphone level programmability" is a contradiction in terms, but there are tons of Symbian devices and tons more that run J2ME.

If you want more than that, you're looking at a smartphone. Just not one you have to install much on.

Err Symbian was/is a smartphone platform...

There are loads of phones from before the iPhone that could play music and run j2me apps that nobody considers 'smartphones'. I wrote apps that ran on the Sony Ericcson T610 but that still gets called a 'cameraphone'.

I know and it grinds my gears all the time. Hell, when the iphone first shipped it was more featurephone than smartphone. But the MSM decided that because there is a touchscreen, there is a smartphone...

While the T610 - one of the first Sony-Ericsson devices - is not a smartphone there were many true smartphones before Apple finally joined the fray in 2007. Devices running Symbian S60 were smartphones and marketed as such in 2000 (Ericsson R380), those running Windows CE/Windows Mobile were smartphones, the Nokia Communicator (1996) was a smartphone, there were several smartphones running PalmOS (starting in 2002 with the Palm Treo), Blackberry sold smartphones, etc.

Just get a device which is supported by one of the alternative Android distributions, build a stripped-down image for the thing and install it. As Android is built on top of a somewhat idiosyncratic Linux base the environment should be recognisable to anyone used to such. You can leave out any code you don't want to have on the thing, add things you do want (e.g. iptables configured before the network goes up, etc).

Using a "feature phone" with "minimal internet and multimedia capabilities" would give a false sense of privacy as the limited feature set does not negate the possibility of the device leaking all sorts of info to the outside. After all, "minimal internet" is still internet and as such can connect to anything out there. Given that even the most limited IoT-device can leak information to its true masters, a "feature phone" is hog heaven for someone looking to eavesdrop on unsuspecting users.

You could build yourself an Arduino Phone.

Here’s such a build, but Googling “Arduino Phone” will get you many iterations:

http://www.instructables.com/id/ArduinoPhone-20-an-Open-Sour...

On a similar wavelength there's the rasberry pi phone: http://www.davidhunt.ie/piphone-a-raspberry-pi-based-smartph... .

Well there's SailfishOs, which just got officially ported to Xperia X. I own a Jolla phone, which was the first to run this OS. It is open source, and I have to say quite hackable, even though I haven't tried to make any apps. Something that I find pretty cool is the fact that you can ssh into it if you enable developer mode, and you basically have a linux machine. The downsides are that the company is no longer making phones, and that there are not that many native apps for it. The upside is that it supports android 4.1.2 apps, so you are going to be covered for the most part.

Those are smartphones by anyone's definition.

Hunt on ebay for a crappy old Windows CE based phone? I've had several (before Android was a thing) and you can program in many languages on them (providing you can still find the apps - I've still got a local repository somewhere). Also the original version of Visual Studio.NET and VS 2005 both supported Windows CE as a target so you could program apps in c# and copy them over.

Windows CE on phones was marketed as 'Windows Mobile' and the latest version was 6.5:

https://www.google.co.uk/search?q=window+mobile+6.5&hl=en&tb...

ZeroPhone [0] matches your requirements. It's DYI, but there's a crowdfunded campaign coming soon [1].

[0] http://wiki.zerophone.org/index.php/Main_Page [1] https://www.crowdsupply.com/arsenijs/zerophone

Maybe get an old smartphone, specifically a Nokia E-series running on the S60 platform. They can run J2ME and C++ apps, as well as Python scripts that can interact with the APIs (networking, camera, accelerometer, etc). And you could install Opera Mobile, which was actually a pretty good browser. Plus a full QWERTY keyboard.

If privacy is an issue for you then build your own phone using a raspi https://www.raspberrypi.org/blog/piphone-home-made-raspberry...

And since that one was made, there is now the RPiZeroW that has wifi and bluetooth built right in.

Surprised there is no phone kit for it already.

Try Tizen OS? Open source and the Z2 phone is so cheap! It's really a smart phone with a different OS though...

Not sure if it's still happening but Samsung had some developer bonuses for apps, so could be lucrative (in the short term)

Probably Librem 5 would suit, but it is still in development.

https://puri.sm/shop/librem-5/

If privacy and software bloat are your concers, have a look at CopperheadOS. It's very slim and offers good privacy. Battery life is incredible!

Can you get one of the google phones and flash them with AOSP?

Why not Ubuntu Touch/UBPorts?

You would need to get a Nexus 5, which is still hard to get below $100 and the price will probably keep high due to UBPorts keeping demand up.

TIL of UBPorts. I thought Ubuntu Touch was long dead.