WWVB Emulator

★★★★★ Excellent app! Does exactly what it's intended to do, and makes an excellent backup when the WWVB signal is too weak or compromised. While it may not be 100% to the precise second (it uses your phone clock which may be off by a few milliseconds) according to NIST or USNO atomic time systems, it still does the job VERY well. The key is to have the phone volume all the way up and hold the phone's speaker as close as possible to the antenna system of the time piece you wish to sync. Works well!!!

★★★★★ I was a bit surprised, but it *worked*. I have had radio-synchronized Casio watches for years, and while they don't get the signal every night (I live on the East Coast, far away from thel Colorado WWVB broadcast), they did pretty well. I recently got a Citizen watch that has been less capable in picking up the signal, so it was about 5 seconds fast. I found this app via Google, installed it on my Samsung tablet, and followed the instructions by boosting the tablet's volume and putting the watch into receive mode alongside the tablet's speakers at about 6:45 p.m. well indoors. The app started emitting clicks and pops, and about 10 minutes later, the watch showed that it had received and synchronized the time, and it is now exactly matched to the tablet (and, presumably the Internet time).

★★☆☆☆ Ineffective. Watch is now approximately 8 months behind. Instructions for 2 to 3 minutes. Tried for 20 minutes. Not as awful and loud as the last app I've tried. But still just as useless.

★★☆☆☆ App works but seems to be about 2 seconds slow when compared to other atomic sources (watch synced via Bluetooth, watch synced via multiband 6, time.is website). I'd rather just manually set it.

★★☆☆☆ Doesn't sync to actual time, syncs watch to the phone's time. If the time on the phone is off, the watch will be too.

★★☆☆☆ Did not work with my Casio GW-9600. Tried with headphones, the phone's speaker, and a Bluetooth speaker. And various volumes on all three. The Casio did show it was receiving, but never sync'd. Maybe when I change phones I'll try it again.