Monday, August 6, 2012

Cache Beacon (beta) - Introduction

This is a post about the Android app Cache Beacon that supports Wireless Cache Beacons on Android.
Garmin® introduced Wireless Beacons in the form of their Chirp™ device almost two years ago.

A Wireless Beacon can contain cache information like cache name, coordinates and hints.
These information is transmitted via the ANT+ protocol. Some of the Garmin GPS devices support these beacons.
Accessing the information from other devices is complicated, because most devices lack an integrated ANT+ chip.

There are solutions for iPhones and iPads by purchasing a separate BlueTooth ANT+ adapter.
Unfortunately these adapters are quite expensive.

Although the ANT+ Geocaching Device Profile is open there didn't exist a solution for Android devices to access Wireless Beacon until now.
Cache Beacon is an Android app that makes it possible to read the beacon information.

Note: The app is still in beta, so there might be bugs.

To use this app a Sonx Xperia device or an Android device with USB host support is needed.

The maximal distance varies from device to device. When testing, the max. distance with the Xperia device was approx. 2 meters. With an USB adapter it was possible to stay up to 4 meters away.

Sony Xperia Devices

There are some Sony Xperia devices that have an integrated ANT+ chip.
The app should work with these devices without any modification.

Sony Xperia pro

Here is the list of supported Sony devices:
Sony Xperia arco S
Sony Xperia S 
Sony Xperia ion 
Sony Live with Walkman 
Sony active
Sony Xperia arc 
Sony Xperia arc S 
Sony Xperia mini
Sony Xperia mini pro
Sony Xperia neo
Sony neo V 
Sony Xperia pro
Sony Xperia ray
Sony Xperia X8
Sony Xperia X10 mini
Sony Xperia X10 Mini pro

The app has been tested with a Sony Sony Xperia pro (Android 2.1).

USB Host Mode

In addition Android since version 3.1 supports USB Host mode together with an USB OTG adapter.
If USB host mode is supported by the Andrdoid device an USB2 compatble ANT+ USB adapter can be used to add ANT+ support.

USB OTG Apter and SUUNTO Movestick Mini

This has been tested with the following configuration:
Galaxy Nexus, SUUNTO Movestick Mini

After starting the app, the app will tell you if USB host is supported or not.

Result Intent

The app can be also called from another app by using a Result Intent.
The Intent Action to use is:

The resulting Intent contains some Intent Extras.
Here is the list:

BEACON_NAMEStringCache NameGC123456
BEACON_HINTStringHintfollow the white rabbit
BEACON_VISITSIntegerVisit Count4
BEACON_LAST_VISIT_DATELongMs since 1.1.19701344249202000
BEACON_BATTERYStringBattery StatusOk


Google Play: Cache Beacon


  1. wow, great app
    so now i can buy a xperia phone :)

    i have an garmin oregon 450, which can send and receive geocaches via ant+

    if i could send caches from my mobile phone to the garmin, if would be sooo great!

    i would pay for this app

    one question:
    would i be hard to develop such an app??

    1. Hmm ... I don't own a Garmin GPS device and I don't know if the transfer protocol is public.
      If it is, it might be possible.

    2. One more thing ... the distance for my Xperia mini pro was only about 2 meters.
      You might be disappointed.

  2. ok,
    i thought u know if the protocol is public or not, as u found the chirp protocol (i didn't)

    also i never programmed for android
    (just a bit java)

    as i own an oregon 450 i don't need the bacon app soo much
    but it would have been funny :)
    i own a chirp-cache myself and therefor 2 meters might be ok

    sending caches to my oregon would have been great, because caching with my oregon is more fun than with my smartphone (currently i own a nokia n8)
    … and sync single caches without usb-otg or the pc should be much more faster :)

  3. Finally! I was waiting for this kind of app for now about 1,5 years. Since there are only 3 beacons hidden near my location the pressure to find them was not to much but still those were tempting. Now I can test it on the field and see how it works.
    Thanks from near the Harz mountains,
    Uwe (nHedgehog)

  4. If I hit:


    "We're sorry, the requested URL was not found on this server."

    Whats the story???

    1. Cache Beacon is no longer available at Google Play.
      The reason is that there is now an official ANT+ Plugin Sampler that includes the functionality of Cache Beacon.
      It also allows to write Chirps which was not possible with Cache Beacon and is more stable.
      Cache Beacon was ok as long as there was no other implementation of the protocol.

      The ANT+ Plugin Sampler can be found here:

  5. "ANT+ September 4, 2013
    "invalid 36046" is the broadcast name of your chirp. Click on that name and it will download the existing info and allow you to program new info to it".

    Unfortunately, clicking on the "invalid 36046" gets "Downloading device data", then "Unfortunately, ANT+ Plugin has stopped".

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