I need international telephony services, so I did a lot of research and tried out various options, and they all are pretty bad. The best I found (if you need data, which I do) was
Truphone (link to
prepaid site, though
I don't recomment the prepaid option). They don't support all countries though, but if I go in a supported country, that's what I will be using.
Attention, for the prepaid SIM data is still pretty expensive, and some countries are orders of magnitude more expensive than others, so do your research before travelling!If you are a business Truphone is excellent because they have business plans (it's very easy to quality as a business, anything goes, really, even one-man operations).
TBH I just use Truphone for data and eat the cost of roaming with my regular home phone number for calls/SMS. I rarely need to speak on the phone (as opposed to some other kind of voice chat) while traveling, usually only for some kind of emergency, and when that happens the roaming cost is not
that bad. Data roaming costs with home plans are generally crazy though, or come with too many caveats (increased latency, 2G only) so that's why I use Truphone.
If you use a new iPad/iPhone, you can use the eSIM functionality, and they have special plans for that. You don't need a physical SIM card. This is
significantly cheaper than the prepaid plans, and this is what I use. So I very much suggest that.
I have a giant list of resources/services about international telephony:
https://xw.is/wiki/Global_telephony. However, it's unsorted and mostly catered to the more technical side of things (running your own SIP server, etc). However, it might be useful to someone.
To summarize, with Truphone look at the eSIM/business options, the prepaid option is generally pretty expensive.
