May be this can inspire others to do something similar. We have built multiple notification capabilities on a mobile app (WEM Optimizer on AppFoundry):
User customizable and separate notifications for paid activities, unpaid activities, appointments, tasks, time off. Users can swipe to select the time interval for each notification.
We believe that this provides some flexibility to enable/disable alerts for different types of activities especially when users are away from their desks.

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Hichem Agrebi
hichem.agrebi@cc-expertise.comCC-Expertise Ltd
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