Get Ready for ANT+

Before you can connect your ANT+ Garmin Device to your tablet / phone, you need to install some additional piece of software and set up a few things in your watch. Here is a detailed explanation of each step.

Step 0: check you Android device

Some android devices have an internal ANT+ chip. A list is being maintained by dynastream here. Note that minor model differences matter: the S4 has a working internal ant+ receiver, the S4 mini and active don't. 

If your device is in that list, you can skip Step 1, as you won't need the ANT+ USB dongle. In Step 2, you need only the Radio Service (don't install other stuff). In most cases, it will come preinstalled. However, you have to set the "force ant+ scan" option in my app.

If your device is not in that list, chances are it does not come with a big, size A usb port, so you might wonder how to plug in your ant+ dongle. The answer is quite simple: you need an OTG cable like this:

Note: it HAS to be an OTG connector. Please don't mess around with other cables. An OTG connector does more than changing size. It has a wire on the micro-usb side tellling the android device to switch into host mode.

An OTG connector is usually cheap (a couple of euros / dollars) and it's generally speaking quite useful. For instance, you can use it to connect a keyboard to your android device.

Some tablets (some Samsung, some Asus, etc) do not have a micro-usb, and require a manufacturer-specific OTG adapter.

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in some [rare] cases, the android device is not bringing power to the usb, so the ant+ dongle won't be powered, and unsurprisingly it won't work. Please read Step 2 on this other tutorial to learn how to supply power. In this case, a y-cable is normally safe as well as the hub.

Step 1: check your ANT+ USB key

A small number of Android devices (mostly the Sony Xperia family) come with an internal ANT+ chip. In this case, you don't need the Garmin USB key. In every other case, you need the ANT+ USB key that you're already using with your computer. Before you go further, check the key version on the bottom: it should read USB2. USB1 keys are not supported at this time.
The app is also known to work with the Suunto Movestick and with the newest "mini" ANT+ garmin dongles.

Step 2: install the ANT+ services

In the end, I decided to base Sportablet on the ANT+ services from Dynastream. Unlike the Garmin ANT+ Agent you install on your PC, those ANT+ services don't know about your Garmin device, but know about the ANT+ hardware (the USB key, the internal chip on Xperia, etc). This should make my app a bit more future-proof (read: I shouldn't have to implement low-level drivers for new keys). We'll see :-). Meanwhile, that means you have to install two free apps (Android services actually) from Google Play:
- The ANT Radio Service (which deals with ANT+ channels)
- The ANT USB Service (which deals with the USB key). If you have an internal ANT+ chip (like the Xperia) you don't need this. See here for details on using an Xperia.

   Go ahead and do it! 

Note that those apps require your Android device to be properly classified by Google Play as one with USB Host capabilities. Some devices, which are host-capable, are not properly classified in Google Play. In that case, unfortunately, the ANT+ services will result "incompatible" with your device and you won't be able to download them. As they're provided by Dynastream, there is little I can do about it - you'll have to find an alternative way to obtain and install the APK (or convince Dynastream to drop the USB HOST requirement from their manifest, as I did for Sportablet). 

Step 3: check that everything works

Insert your USB key. If you have a micro-usb connector, remember that you need to use a USB OTG adapter. This dialog should pop up from the ANT+ Service:

of course, you have to accept.
If the dialog does not pop up, your USB key is not being recognized by the ANT+ Service. That's not part of Sportablet, so I can't really help you much on this side. Please check the Google Play page for the two ANT+ Service apps, as there are quite a few hints from users in the comments section.

Now, if you want to double-check that it works, and you have a chest strap that you use with your Garmin, you can also download the free ANT+ Demo from Dynastream. It's a simple app that can connect with a chest strap or a scale and show you some values (it won't connect with your Garmin, just with the HR belt). If the ANT+ Demo works, everything has been set up properly. If you don't have a chest strap, just skip this step.

Step 4: configure your watch

It's time to fiddle with the bezel a little and make sure ANT+ is properly set up. Although you've probably done this before to pair your Garmin with your PC, you have to do this again to enable pairing with your Android device, and to make sure that all the activities in your watch will be sent. The following pics are based on a Forerunner 405.

Choose Settings > ANT+ > Computer

Make sure that:

Enabled is set to yes

Pairing is set to on

Force Send is set to yes

Note: the watch will change "force send" to "no" after any successful upload. If you upload from your Garmin to more than one device (like your tablet + your pc), you have to set it back to "yes". The Garmin does not remember to which device it has sent data, and by default it is only sent once.

Step 5: it's time to run Sportablet!

Run Sportablet. Don't click on Get new yet. First, make sure that your watch is not in stand-by, by clicking the top button. I've found that the watch transmits more reliably while in Time mode:

note: this part is no longer necessary with the latest version, I'll remove it as people upgrade:
UPDATE (July 2014). Due to a new version of the Dynastream Service, before you click get new please get into the options, scroll down to the ANT+ section, scroll down to the last entry (it should read "Force Claim Interface") and turn that ON. This is usually needed only if you use the ANT+ USB dongle, and not necessary if you have a built-in ANT+ chip in your phone.

Now click the Get new button. You may see that the app is trying to connect on different frequencies: that's ok as it's part of the ANT+ protocol. After a while, the app will ask you to accept pairing on your device:

do so by clicking the top button on your watch. After that, it should proceed as usual: Runs are downloaded, then Laps, then Tracks. At the end, the dialog will report how many new activities you got. Click Done to get back to your main screen. 

NOTE: if you're using an Xperia or another device with internal ANT+ chip, remember to click options, and set "Force ANT+ scan" on. This will force the app to try using the internal chip.


NOTE: it is often necessary to set up a few options in the app, as well as to set up your tablet / phone properly. So, if the process fails or times out, please read the following section. It is *very* important that you turn off wifi / data / 3g / etc on your android device.

Tweaking : )

ANT+ has very delicate timings, which can be easily disturbed by background processes, especially in a smartphone. So if you experience problems, the first thing you should do is turn off the GPS, Bluetooth, WiFi, data connection on your phone. This is known to help a lot, and honestly, is basically mandatory.

ANT+ is not particularly good at transferring long sequences of data, and the protocol Garmin adopted on top of it for the 405/410 family does not allow to retry on failures, so the combination is a little flaky on some devices. If you have any problem downloading long activities, Sportablet and the Uploader provides a few settings that you can try (under "options")

- First, make sure that diagnostics is turned off. ANT+ is very time sensitive, and on some devices even the time spent on logging seems to cause problems.
- Next, just enable "Delay Ack". Leave all the other ANT+ options off. This should give the watch a little more time to synch with the tablet during long bursts.
- If that still fails, turn "Boost TX power" on.
- If you still have problems, get in touch. The other settings are not effective for a 405/410.