[Nexus 4 General] mm2001:
My Real World results with voip for 4 months

Just how good is using data for voice calls on the T-Mobile $30/mth plan to get around the 100 minute limit? This is my experience over the past 4 months.

TL;DR: Unless you happen to be in an area with superb T-Mobile coverage AND you don't expect to talk while driving, it ain't going to work all the time. Have some extra credit on your account and expect to pay for some minutes every month. Train your frequent callers to expect you to not answer and call them back.

The longer version:

Background:

I have great T-Mobile coverage at my house. I can talk on the phone using voip pretty much all day, using either T-Mobile directly or my home WiFi. (Voip doesn't use much bandwidth, so I don't obsess about it).

I'm using the Google Galaxy Nexus and the built-in SIP client. I found every other client had problems with my Bluetooth headset or integration with the existing dialler or contacts, or was just plain buggy.

I haven't configured inbound calls to use VOIP to avoid draining the battery. Thus, I'm not using GV either.

I tried Vonage for a while and it was absolutely the easiest setup to use by far. I ended up switching to a FreePBX box that I had already and using a GSM codec, but in hindsight, I think Vonage would have been fine for reasons explained below. (I'm sure SPEEX or G729 would be better, as others recommend, but I couldn't be bothered setting them up, plus the built-in android SIP client doesn't support SPEEX).

Learnings: "its the coverage stupid"

My first experience was "wow, this all just works". However, as I used the phone more, voip calls would have problems. I drove my business partner crazy, and my wife refused to talk to me on my new phone. Over time, patterns began to emerge. It turns out that right near my house, on the way to the freeway, there is a dead zone. This zone is so dead that even regular cellular calls will drop, every time. (Ironically, data calls work better here, because if traffic is right I can zip through it with only a little lost talking without the call dropping.)

So now, when I'm around home / on my usual routes, I know where calls will work and where they won't and I can plan accordingly. E.g. I wait to get on the freeway before starting a call that I know is more than a few mins. Or I just accept that I can't call when I'm at my favorite lunch place (there is just barely Edge coverage there).

I've also learned that time of day is important. Going to the airport at 6am is fine. Coming back at 5pm sucks. Between slower traffic and presumably more congested towers, sometimes it will work great in a given place but not at other times.

Be prepared that some calls will be great, you'll be stationary, and then they'll go to hell for 10-15 secs, and then they'll be great again. This seems to bite me most when I'm calling from somewhere new.

Where I'm at

I have come to accept that the plan will cost me about $40/month (i.e. with about 100 extra minutes a month). This is still a crazy good value plan, and it works great with my Galaxy Nexus (and presumably will be great with the N4).

When the call "has" to work, I either call from somewhere I know I have great coverage, or I use cell minutes.

Friends know I'll call them back.

I'm going to give Vonage another try

I hope this helps some people. Happy to answer any followup questions.