TwitCharts is a web service provides draw charts for your data by specifying data entries and their values and, then tweets the chart easily. TwitCharts provides different draws for charts (2D pie, 3D pie, lines..). It also provides an API for developers.
Pros & Cons
|Uses OAuth for Twitter login||Some of the results are not correct|
|Provides different types of charts|
|Provides an API for developers|