I used the Time shifter app as an experiment for a trip I had to make from the East coast to the West with only a 2 day turn around. I flew out late on Thursday night, had a 21 hr day and a day long meeting to attend on Friday and Saturday. I was afraid I’d be a zombie but I felt great! It’s hard to believe but I actually felt great. The instructions are easy to follow and are simple. I will never make a long trip without using Time Shifter! It made such an enormous difference in the quality of my time while on the ground in CA and once I got back home as well. I really can’t say enough good things about it.