The first week of real traffic showed us two things worth fixing straight away. Both are done.
At launch, delivery status was read back from the operator's dashboard: campaign totals, polled a few times an hour. Fine for "how did the campaign do", useless for "did number 0123456789 get it". We have now moved sending to the operator's official system API, which pushes a receipt to us for each number the moment its status is final.
What that means for you: the Send history now shows delivered and failed per number rather than as a campaign percentage, the "Processing" state clears in minutes instead of an hour, and the numbers in your report are the operator's own, not our interpretation of a dashboard.
An early customer sent a Chinese-language message and the recipient saw question marks. The cause was an encoding flag on the upstream side that does not follow the usual convention. Fixed on day one; the console's encoding indicator (GSM or Unicode, with characters per segment) shows exactly how your message will be sent and billed.
While we were there we verified our segment counter against what the operator actually bills: 160 characters per segment for plain text and 70 for Unicode, dropping to 153 and 67 once a message needs more than one segment. The quote you see before sending is the amount you are charged, and the amount we are charged. There is a segment calculator if you want to check a message before pasting it in.
Free trial credit, real delivery report, no contract.