I would also agree with the request to add an On/Off Switch for the next Mooshimeter version.
I don’t use my multimeters continuously, for my “use case” a switch would be very helpful. Good batteries (energizer ultimate lithium, e.g.) have a much energy and a lifetime of 20 years. You will probably never need to replace batteries when using the multimeter some hours a month.
@Chad: if your mooshimeter eats to much energy, please check if the logging is activated (periodic write operations to SD card will take down the battery quickly).