Smartphone shipments can rise to account for over 1/2 all cell phones for the primary time. pill PCs like Apple iPad and Google Android-based tablets additionally boost the employment of non-public task management applications in our everyday life.. In general, tasks can be broadly classified into two categories: (1) time-based tasks, (2) location-based tasks. If a task is timebased, we mean that the task should be carried out at a specific time. For example, taking medicine at 9 p.m. every day is a timebased task. To remind ourselves of this kind of tasks, we can set an alarm in the personal task manager to make a “just-in-time” prompt. On the other hand, if a task is location-based, we mean that the task should be performed at a specific location, such as to buy a bottle of milk at the convenient store nearest to your home. In this case, setting an alarm triggered by time may not be appropriate if you are not sure when you will be passing by the convenient store. This motivates us to design a location-based personal task reminder, which can provide a “just-in-place” prompt to users .