Comica CVM V30 Lite - Value Super Cardioid Mic
Though not perfect the Comica CVM-V30 Lite is a reasonable sub $40(USD) Super Cadioid Microphone. This polar pattern is great for people recording a subject directly in front of them. Be aware that with this polar pattern directly behind the microphone is picked up well. This is both good and bad as the Camera man is now very clear if talking with the subject but also the sounds of loud focusing rings can be heard.
For best performance when using on a cellphone or tablet turn off wifi or better yet switch to airplane mode as it will remove large amounts of interference. This also goes for DSLR's as the bass sound I referred to in the review is removed when bt/wifi is turned off.
Super-Cardioid Polar Pattern
Support Smartphone & Camera
Excellent Shock Mount
No Battery Drive Design
Super Low Noise Electronics
Cold-shoe Design with 1/4 Thread at the Bottom
Compact and Light, Easy to Carry
As stated above the Comica CVM V30 Lite is not perfect but for its price it really is a must try and must use for education and beginners.