What calendar or clock will be used once other planets are colonized?

Since time as we know it is for the most part based upon the physical dynamics of the Earth’s movement through the solar system, what system of time will be used on say Mars once it is colonized? Using the 365 day 24 hour calendar would be a real mess on Mars since it’s orbit around the Sun takes nearly 700 days and it’s daily rotation is almost 25 hours.

Would it make the most sense to have “Earth Time” become a universal standard time that is converted locally similar to time zones?

What are some ways this has been dealt with in Science Fiction?