TaroWorks currently permits each form submission to include location information and in the future will support other features such as tracking location per task and tracking location as a question type.
Here are some important technical considerations when using the Location Services in conjunction with TaroWorks:
- Android devices in general has 3 ways to determines its location: Mobile Network Data Signal, Wifi Signal and GPS receiver (if equipped)
- Location using Mobile signal needs an active data connection
- These needs to be enabled in the Setup menu of the android device to function.
- In general, GPS is the most accurate (accurate with a few meters), followed by Wifi (usually within 20-40m) and finally Mobile Data signals as the least accurate (100m at best, usually 600m to over 1km)
- Getting a location can take 5 second to 5 minutes depending on if the device is ready.
- You can help the GPS find it's location faster by also turning on the Wifi (if a signal is present) and Mobile Data
- Note that using the GPS receiver requires a clear view of the sky and drains the battery the fastest.
- In general, inexpensive lower-end devices will have less accurate location readings.
- The first time a device finds itself at a new location, it can take up to 20 minutes get a GPS fix. If possible turn on the device and get a fix before you or your Field Staff sets out with the device. This will save the time in the field. Getting a GPS fix on all the Androids updates the almanac data and the next fix in the same city/village/area will be much faster.
- Almanac data assist in speeding up the acquisition of satellites (faster location fix) at power-up by allowing the device to generate a list of visible satellites based on stored position and time, as well as increasing the accuracy of the readings.
These are the implications:
- Note that what TaroWorks does is to grab the last known location stored by the Android Operating System. This means that if you get a GPS lock outside then turn of all networks, move to another location and record the location again you would be given the old location, which might be very different from where the device currently is. This is also the behaviour for Google Map and ODK. IMPORTANT: For this reason, it is best for your field officers to take some time to check the accuracy before recording the location into TaroWorks.
- Consider the accuracy of the device and the application you are using it for. If you are planning to record location of houses that are 2 meters apart, but the device accuracy is only good within 200m, then the location collected is unlikely to be useful for your purposes.
- Currently there are no plans to enable automatic identification of objects from the location information alone. (Ie. You cannot collect information on a school and have it automatically be associated with that school simply by taking a coordinate reading on site.) We recommend that you continue to use unique identifier codes, QR codes or unique names to represent such objects.
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