We want to use the collector app to manually register water levels. At the moment appr. 10% of all registered values does not pass the validation rules (a minimum and maximum value), frequently because people forget the minus character (1.23 instead of -1.23). Now we have to "correct" or dismiss the value afterwards. It would be better if the value could be checked at the spot (online or offline) before saving the result, for instance by showing some kind of message or by highlighting the value. In most cases the value would immediately be corrected. Of course sometimes exceptional levels do occur and it must be possible to register those values. To complicate things the minimum and maximum value depends on the location and are stored in two separate fields. Does anyone know if this kind of on-the-spot validation in the Collector App is feasible?