SyncTime: JJY, WWVB & MSF

Radio controlled atomic time syncing: JJY, WWVB & MSF emulator/simulator

App info

Version :

Category :

Tools

Update :

August 29, 2025

Installs :

256

Developer :

SWard Dev

Price :

$3.99

Requires Android :

Android 5.0+

Content Rating :

Everyone

App description

Android App Analysis and Review: SyncTime: JJY, WWVB & MSF, Developed by SWard Dev. Listed in Tools Category. Current Version Is 10, Updated On 29/08/2025 . According to users reviews on Google Play: SyncTime: JJY, WWVB & MSF. Achieved Over 256 Installs. SyncTime: JJY, WWVB & MSF Currently Has 19 Reviews, Average Rating 4.9 Stars

SyncTime syncs the time on your radio controlled atomic watch/clock — even when the time signal radio station is out of range.

SyncTime is comprised of a JJY, WWVB & MSF emulator/simulator.

Why Use SyncTime?
- SyncTime is completely silent.
- SyncTime allows you to override the timezone with any timezone of your choice.
- SyncTime uses NTP time for the most accurate time (requires internet).
- SyncTime allows you to sync the time when the screen is off or when SyncTime is running in the background. This feature is device dependent as some devices may close or mute SyncTime.
- No Ads.

Supported Time Signals:
JJY60
WWVB
MSF

Due to the limitations of physics and the speakers used in Android devices, these time signals are the only signals capable of being supported whilst also being fully silent.

Instructions:
1. Turn your volume up to the maximum.
2. Place your radio controlled atomic watch/clock beside your speakers/headphones.
3. Activate the time sync on your watch/clock.
4. Select the time signal supported by your watch/clock.
5. (WWVB only) Select the timezone that is set on your watch/clock. Timezones include Pacific Time (PT), Mountain Time (MT), Central Time (CT), Eastern Time (ET), Hawaii Time (HT), and Alaska Time (AKT).
6. Press the play arrow to start syncing. After approximately 3-10 minutes your watch/clock should be synced.

Note: Watches/clocks which have a 'home city' setting may need to be set to a city which can receive the official radio station time signals. After syncing, the 'home city' can be reverted.

What's New

Added support for 16 KB memory page sizes.

Rate and review on Google Play store

4.9

19 total

5 94.4

4 5.6

3 0

2 0

1 0

Total number of installs (*estimated)

Estimation of total number of installs on Google Play, Approximated from number of ratings and install bounds achieved on Google Play.

Recent Comments

David Root

Did not work on the first try. Followed up with a couple of adjustments on my phone. Now it works fine. Great that it is silent. I want to add a couple of comments that may help other users: 1. On my phone, if Bluetooth is on; my phone plays to my hearing aids. Since the app is silent a user may not immediately grasp why the app is not working. 2. It may be useful to determine the interval at which the phone itself syncs with NTP. I have observed variances between phones and my WWV clock.

Brandon J

Best app for the job! I own a Citizens pmd56-2952 and literally no other app would sync the time correctly with JJW time. The ability to choose a time zone to override is brilliant and within 10 minutes, my watch was synced and accurate. I cannot recommend this app enough. Huge plus that it doesn't collect user data, as I'm very privacy conscious. Great job dev! I'll be plugging this on forums from now on.

Danny Mann

It does what it says. It's not silent, but I'm not too bothered by it. One issue is it doesn't send DST. You can work around by setting the timezone override, but the timezone you have to override to makes very little sense. I set it to ETC/-1GMT to get it to advance my clock forward 1hr for DST. It would be better if there were a checkbox to send the flag for DST as my clock picks that up and even changes the timezone to indicate DST. I tested and confirmed the real WWVB signal sends DST state.