No. While it is correct that the app will upload your recent pump data into your t:connect account when connected to Wi-Fi or you allow cellular data usage, uploads do not happen in real time and the t:connect web application is not intended to be used as a tool for remote monitoring.
For Dexcom continuous glucose monitoring (CGM) specific issues including calibration prompt will not clear, sensor failure during the 2-hour warmup, “no restarts” alert or physical problems with your sensor or transmitter, such as bleeding, bruising, skin reaction, adhesive issues, applicator issues, or broken wires, please contact Dexcom using one of the options at dexcom.com/contact or report the issue online at https://dexcom.custhelp.com/app/webform.
Please see table for a full list of who to contact for Dexcom CGM issues.
Tandem handles issues such as loss of connection (on pump only) and the invalid transmitter (Alert 29) on pump only.