roman You probably have an older phone and tablet where some HTTPS certificates are no longer valid. You need to update Elementary POS to the latest version. Currently 3.54. You can update via Google Play. If you don't have Google Play, you can do the installation manually. The app can be downloaded here: https://elementarypos.com/en/get-free-cash-register-pos-system/ OR (without https, usable for older devices): http://bawadu.com
