How do I use all my phones?
Short answer - They all work well together.
Long answer...
Microsoft Lumia 640
+ Pictures and video recording since it actually takes the best ones.
+ Clearest and loudest voice quality. Kudos, Nokia.
+ Loud speaker equal to my LG.
+ 3rd best battery life.
+ Pocket Wi-Fi (hotspot) for my other phones.
+ Texting since my Smart sim is the only one to get signal in my room.
+ The workhorse phone right now needing to be charged often since acts as the Pocket Wi-Fi device for the others.
+ Removable battery and sd slot
- Don't use it to web browse much since I prefer to do it on Android.
- Viber, Netflix, and MX Player is weak for WP. No Instagram or Snapchat. Can't web cam with FB Messenger either.
- YouTube video downloading apps NOT as good as TubeMate.
- No Camfrog! Aww! But it can record the showings. Yay!
- Great Nokian hardware only bogged down by Microsoft software.
Motorola Moto E2 4G
+ Wi-Fi browsing
+ Best battery life going beyond 10-12 hrs easily.
+ Longest Wi-Fi range surprisingly beating the Xiaomi which has Wi-Fi ac.
+ Fast and fairly smooth UI.
+ Perfect ergonomics better than iPhone 4, 5, and 6 series. Perfect height.
+ Use it when I travel to town since it rains alot and has water-resist nano coating and more compact.
+ Media playback because the speaker is in the front so when I lay it down, it doesn't muffle the sound.
+ Favorite to use at the moment because long battery and so comfortable to hold.
+ If either Lumia or Moto ever got stolen, hey, they were only $30. *shrugs*
- Poor camera and voice quality though.
- No LED flash
LG G3 Beat
+ Rooted
+ Removable battery and sd-slot
+ Dual sim
+ My gold draws the most glances (fashionista phone)...
+ Everything the Moto E2 can do especially for media storage but with a better hardware for camera and HD display.
+ 2nd best in reception and camera to Lumia and loud speaker equal to it.
+ 2nd best battery life
+ Strongest LED flash
+ Fav design that I own and only non-black front.
+ Doesn't overheat like my HTC One M7 did after 20 minutes of PvZ2. Modest matte plastic exterior and Snapdragon 400 at 1.2 GHz helps it keep cool and with longer gameplay (6-7 hrs over HTC's 3-4 hrs)
+ My current favorite because although it seems kinda laggy with its LG skin, it doesn't have any major weaknesses after that. Either 1st or 2nd at what it can do while having my favorite OS on it.
Xiaomi Mi 3
+ My oldest phone which I use mainly to download videos.
+ My fav to use for Camfrog or anything with nude women.

Naughty, naughty, Chinese-made phones that spy on us.
+ Favorite to use for ebooks since Moon+ Reader is the fastest for it.
+ Best for browsing.
+ Daily driver from July 2014 - April 2016
+ Games because it has the best GPU
+ The first Android that offered me 10 hr SOT when I first got it.
+ The first Android that taught me not to pay so much for phones and be a tightwad. A $250 phone with better specs than a Nexus 5 or as fast as a Note 3!
+ Dropped it twice on tile, no cracks on the screen. Durable.
+ Only Android I have upgradeable to Marshmallow.
- Non removable battery degraded after 20 months. 4th best now which is why I don't use as much. Equal now to the iPhone 5 (5-6 hr SOT) I used very briefly last year.
- Limited storage space (6 GB avail) where practically all my photos was cleared out.
- Other, newer, and cheaper phones I got surpassed its camera and its video recording is fairly bad now.
MyPhone my81 DTV
+ Rooted
+ Removable battery and sd slot
+ Dual sim
+ My most rarely used phone but got it because I have no TV signal in my room.
+ Basically helped me out when the 2016 NBA Finals was on.
+ Radio is very loud and clear.
+ Only "4 screen but it helped me see if I could live with an iPhone SE. Doable but prefer the Moto E2 comfort and size.
+ Surprisingly has the strongest signal because it could get a Globe signal in my room while the other phones can't. Not bad for a $38 local branded phone.
- Worst screen which inverts the color when you tilt it a slight. Although viewing angle not affected when the DTV is on.
- Worst camera (front and back)
- Worst battery life comparable to a Nokia X with comparable specs. Sub-5 hr SOT for video and web.
- On Lollipop but most laggy with Spreadtrum SoC with only 512 MB RAM.
- Only ONE channel I get but it was good enough to watch the NBA Finals since it was on it.
- Least favorite to use since it has specs comparable to Android flagships from 2009 but at least it has a built-in DTV receiver and it can record the shows.
Future
Apple iPhone 7
+ When traveling and swimming to take photos. The travel and beach phone!
+ Games since the GPU will likely be fast and more available in the App Store.
+ Re-download all my paid apps I bought from over half a decade ago.
+ Planning to move the Smart sim inside the Lumia into the iPhone. So however I use Lumia now, iPhone will do it.
+ Prefer the web browsing on iOS over WP but not over Android which has CM Browser and Opera Mini and ability to download files other than images.
+ iOS has better apps than WP, especially since it has Camfrog! ;-)
- Media playback I prefer Android, WP, then iOS. Hate iTunes and doesn't have a file manager as good as ES File Explorer and Microsoft's Files. I prefer folders to store my media.
- Likely my main phone since my Smart sim will be in it which is also tri-cut to nano, but at best, my 3rd fav overall phone to use which mirrors my ranking with mobile OSes.
Like watching The Avengers help each other out with their specific talent/skill-set or playing Final Fantasy games. You have a party with multiple characters. You figure out how to use each party member for certain situations. That's how to juggle phones similar to The Woz who juggles like TEN different phones.
Each phone has each other's back and a specific job to do. A phone/OS' weakness could be another phone/OS' strengths and vice-versa. Nobody should be obliged to take sides. They are all great in their own way. Fanboyism only breeds hate and discredits something you may start to appreciate much later. Love conquers all.
Think Different.
Be Together. Not The Same.