My wife is visiting her sister in Canada. We live in the UK. She emailed me last night to tell me that she is unable to send or receive texts on her Nexus 4. Before she left I disabled data roaming and mobile data. My understanding is that she should be able to use the Nexus 4 to make and receive calls and texts without using data.
Texting (a.k.a. SMS-ing) and MMS-ing function over
mobile networks only! Even when you're (she's) connected via WiFi. So in Canada she needs roaming and mobile data enabled if she wants to text or MMS.
At the same time she needs to be aware that texting and MMS-ing are by far the slowest and most expensive ways to communicate (they are the only way the telcos can make money off of traffic). Texting and MMS-ing will consume her monthly dataplan
fast! To boot MMS-ing is only capable of handling very small (= lo-res) picture and video files. One at a time. Neither she nor you will want/like any of that.
The 'IM' protocol, Instant Messaging, OTOH, uses the internet to connect sender and receiver. Which is free!
So I would recommend your wife keep roaming and mobile data off while in Canada, and both you and her install and use (an) IM app(s) to communicate, which will then work only when you and she are connected via the internet/WiFi = free of charge.
My fav IM apps are free
Telegram (fast, secure, can send/receive hundreds of hi-res photos or up to 1 GB of video) and also free
Viber (includes audio and video calling).
Of course if your wife wants to text/SMS or MMS with her sister, while both are in Canada, your wife will need to have roaming and mobile data enabled. Works perfectly, if slow, but is expensive as hell. But if her sister also installs
Telegram and/or
Viber and they both use that, then everything will be hunky-dory (= free).
Once that was rectified all was well.
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