Working with labels is explored with the examples of messengers Viber, Telegram, Facebook. Other messengers don’t support deeplink.
WhatsApp also supports the use of labels - you need to paste a special variable in the automatically filled-in input field that the user gets as soon they click on the link.
Saving the labels
If you add parameters to the link to the mini-landing, all of them will be transferred to the temporary transactions.
More on that here: