Design Widget to interface with Sensor using Geckoboard platform


There are mobile widgets available in my phone I need to what is the possible way to design a widget for temperature sensor?
How can I use .xls format to design the Line graph (shows live stream data) and Pie Chart Show(average data)?
I am trying to connect wireless sensor of My home with smartphone,
Also create an alert notification system which share the notification of alert when ever the sensor reads the data more or less than the defined range .
Please share your expert advice on this .