Hi @Lobe,
we were able to integrate directly with IFTTT in the meantime and we are therefore encouraging users to migrate to that way of integrating.
We are trialing a more strict REST API that does not allow data updates via GET - you can check it out here: Apilio web API v1
But generally speaking, sending data via GET request is not as risky as many believe. Apart from the hostname, the URI and all data is in fact encrypted. A nice explanation is here: https://https.cio.gov/faq/#what-information-does-https-not-protect or of course directly at the source: https://www.ietf.org/rfc/rfc4366.txt