based on specs:
kyocera:
- 5 inch display but with low resolution (540x960)
- says it has Android 5.1, the latest version of android so that's nice (it's an LCD display)
- water resistance is a plus
- 5 MP camera, records at 720p (i don't think it has a nice sensor so pics won't be too good)
- 2 MP front facing camera (not that band, but again depends on it's quality)
- 1 GB of ram 1.2 GHz processor, not thaat bad, the screen isn't too big and the camera isn't that powerful so it won't have to work too much, it must be enough. The multitasking might not be the best tho.
- 8 GB really low, keep in mind the OS is inside so you might get 6 or 4 GB to use for your own apps and media
- The Battery is decent, the big screen might cause a lot of battery usage but again, the resolution isn't that high so i don't think it'll waste as much as it would with an HD display.
- released in 2015 so you might get some updates to newer android versions.
lumia:
i really don't know because i've never worked with windows phone, you'll have less apps than in android (apps like twitter, vine, facebook are available but apps like youtube aren't) you'd have to check for the apps you like in the store to see if they're available on WP.
based on specs:
- released in 2015 as well
- 5 inch display with HD resolution (720x1280) (LCD display)
- 8 GB internal memory (again, low memory available for you to use but windows phone is lighter i think)
- 1 GB RAM, i think with WP 1 GB is enough you don't need as much RAM as u need on android for it to work smoothly
- 8 MP camera with Full HD recording
- 1 MP front facing camera
- 2500 mAh a little big bigger than kyocera, but has a bigger resolution so it might last the same as the other phone or maybe less (depends on the OS as well)
- FM Radio
camera test pictures:
http://www.gsmarena.com/piccmp.php3?...&idPhone3=6638
galaxy:
- released on nov 2014
- 4.5 inch display (smaller than the others, 480x800 resolution)
- 8 GB internal memory (samsung is known for adding "bloatware" to their phones so you'll probably get like 5 GB max)
- 1 GB of RAM running android KitKat upgradable to 5.0.2 Lollipop i think it'll work nicely
- 5 MP camera, 720p recording
- 2 MP front facing camera
- FM Radio
- 2000 mAh, it's the one with the smallest battery of the three but the screen is smaller and has lower resolution so it might last around the same
camera test pictures:
http://www.gsmarena.com/piccmp.php3?...&idPhone3=5958
- the lumia phone has the best specs but it runs windows phone
- the galaxy phone doesn't have the best specs but it's still really nice, it probably has some added features that you might like
- kyocera, i really don't know it has some decent specs but that big screen with low resolution might not be the best. the best feature is that it's waterproof and that it comes with the latest android version out of the box. I couldn't find the camera testing for that phone
here some reviews:
- Lumia 640:
https://www.youtube.com/watch?v=gyzrUF6RQr8
- Kyocera Hydro Wave:
https://www.youtube.com/watch?v=I1I3irt7EWs
- Galaxy Core Prime:
https://www.youtube.com/watch?v=n_uHx3TXbY4
they look great
but im not sure 
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