telegram & whatsapp different in check mark mean .
in telegram : clock mark ( O ) mean message delay in delivery . single check mark ( V ) mean message received but not read . double check mark ( V V ) mean message readed .
in whatsapp : single check mark ( V ) mean message delay in delivery . double check mark ( VV ) mean message received but not read . double blue check mark ( blue VV ) mean message readed .
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