Being in Konstanz, Germany and your phone connecting to Switzerland
Be careful if you're in Konstanz—your phone might connect to a Swiss carrier in certain spots (for me, it was a parking lot near Switzerland and on Mainau Island). You could be charged at least 30 € for roaming if your phone stays connected. I'm with Poste Mobile.
For those in France near the Swiss border, don’t stay in roaming mode. For those like me in Germany, turn off mobile data or get a Swiss plan for 15 €.
For those in France near the Swiss border, don’t stay in roaming mode. For those like me in Germany, turn off mobile data or get a Swiss plan for 15 €.