How to check balance of German SIM card: Telekom, O2 and Vodafone, Germany

Germany: There are three major cellular operators in Germany, Telekom, O2 and Vodafone and are offering all type of plans including few plans with limited minutes, fix data allowance etc. Some customer, including new and tourist or business personnel may not keep track their usage and get surprised at the last moment when alerts are received. It is better to keep a watch on usage and to get...

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