Electronic device with multi-angle positioning support

An electronic device comprising:

• a back cover defining a first contact area;
• a support pivoted to the back cover by a pivot shaft, wherein the support defines a second contact area contacting the first contact area, and a plurality of positioning holes are defined in and disposed on the second contact area around the pivot shaft;
• and
• at least one retractable spring ball projected from the first contact area of the back cover, configured for cooperating with the positioning holes of the support;
• wherein when the support rotates, the at least one retractable spring ball slides out of a corresponding one of the positioning holes, and when the support is at rest, the at least one retractable spring ball slides into a corresponding one of the positioning holes to maintain position of the support.