If you are writing many tags at once: On the phone app, click on the triple dot button in the top right, and click Write tags.

Select the name of the sample site you want to write the tag for. Bring the phone close to the tag, you should see a notification saying the tag has been written.

If you are only writing a single tag: On the phone app, go to ‘Samples’, either use the map or the list to select the sample site you want to write the tag for. Go to the Map tab. Select the triple dot button in the top right and click Write tag. Bring the phone close to the tag, you should see a notification saying the tag has been written.

If you also want to add the GPS location to your tags as you go, follow these instructions.