The Hunt for the Ultimate Free Calling App

In the hopes of reducing my monthly smartphone bill, I've been investigating the current state of VoIP and its potential to completely replace the traditional mobile phone.  I made a list of just about every free calling app/service I found on the iPhone app store.

Specifically, I was looking for a VoIP service boasting these features:
* Inbound phone number, particularly a Japan phone number (e.g. 050...)
* Call recording - not a must-have, but would be nice for when I crank-call friends in the USA

Here are my snap impressions and notes I made during my research.

Services I actually tried...
Line
* Japan-focused and hugely popular in Asia
* Games and stickers allow for communication solely through cute icons--what fun!
* light--loads quickly and doesn't drain my phone's battery as much as other apps
* I have a security concern.  Please see this: Flaw in LINE Causes Unintentional Identity Theft

Skype
* inbound numbers in multiple countries (including Japan)
* call forwarding
* massive user-base
* available for almost every platform
* lots of features, but oddly enough doesn't offer call recording (it can be done with a separate app, though)

Voxox
* inbound number (USA / Canada)
* call recording feature, but I couldn't figure it out
* phone number verification
* can purchase credit though iTunes

WePhone
* call recording feature, and it works!
* 3 different rates to choose from, with varying quality
* can purchase credit though iTunes

Services I briefly looked at...
050Plus
* Japan-focused (run by NTT)
* 315 yen monthly charge
* 050 inbound number
* phone number verification required

Facetime / iMessage
* Apple-only (?)
* connects to your Apple ID
* I worry about Apple stealing my address book after enabling it

Google Voice
* not considered "true" VoIP--just forwards to your phone
* requires Gmail
* believe it or not, it's not highly rated

KakaoTalk
* Japan-focused (run by Yahoo Japan)

Line2
* inbound number (USA / Canada)
* monthly fee for advanced features
* seems to target the small business market

ooVoo
* seems to focus on video

Talkatone
* Google voice client

Viber
* it looks like it sucks your contacts up to the cloud

Voxer
* like a walkie-talkie

Others I found...
Fring
Pinger
Tango
TextPlus
Vonage

Softphone Apps
These are apps that can be used with various VoIP services (that don't have their own app), PBX servers, etc.  I considered building my own server using Elastix, but for now that seems a bit overboard.

3CX
AGEPhone
Bria SIP Phone - counterpath.com
Media5-fone
Zoiper

Learnings
1. VoIP is great for cheap outbound calls.
Most all VoIP services offer free calls to those on the same service (e.g. Skype-to-Skype) and lower rates for other outbound calls (e.g. to a phone number), so this is where they really shine.  Few services go beyond this.

2. Inbound calls are another story.
Very few offer an inbound number.  Even fewer offer inbound numbers in multiple countries.  And several services that do offer an inbound number require phone number verification.  Isn't that a catch-22?  Maybe I don't have a phone number, which is why I want an inbound number in the first place!

3. VoIP is not yet a full replacement for a normal phone.
See #2.  Oh, and you can't call emergency services using VoIP.  Bummer.  I hope I don't die.

4. Protect your little black book.
Welcome to our FREE app!  Now please upload all your personal data to our servers.  Hmmmm...I'm not a big fan of apps that start that way.  Are you reading this Apple and Google?  There's little difference these days between a free "cloud" app and data-stealing malware.