What I like about apps is that they record when I was able to stick to my fasts and how often (I don’t always succeed.) The premium version of Zero tells you what metabolic phase your body is in (very rough estimate, it’s more motivating than educational or accurate.) It just comes down to motivation I guess! I doubt many people on here forget when their eating window is.
I don’t use apps myself, don’t have much use for them.
Just a piece of advice, maybe try to ease into fasts a little bit. If you don’t feel like fasting 16 hours immediately start with 12 hours, and build up on it every day or every couple of days you add an hour.
Shifting your fasting window a bit is not that bad. I do that all the time. I have days where I work in the morning, and days I work late. When I wake up very early I can’t always wait till noon, but when I can sleep a little longer I can easily fast a couple more hours, and sometimes even end up eating only 1 meal a day. This doesn’t stop me loosing weight.
I think the most important thing for me is to stay away from candy and cookies at night.
Concerning the hot water: I drink a lot of good quality loose leaf tea all day. I just like that a lot, and it has a bit of sweetness without breaking a fast. Caffeine can even help with the fat burning process.
I find sparkling water to also help quite a lot, it gives me the feeling I have something in my stomach.
Congratulations on deciding to improve your life with IF!!
You might consider trying to ease into the fasting window over the next 2 weeks. It might help cement in your mind that you are doing this, not just planning to do it at some future date - works for me at least.
For the shifting windows, I believe the most important thing is that you hit the 16 hour mark consistently. So what I do is just like you suggest, if I know I need to eat a little earlier the next day then I shorten my window the previous day. But also, keep in mind IF isn’t a sprint, if you miss by an hour occasionally then don’t beat yourself up, just try to hit it the next day!
I use the apps to remember how I did and as a quick way to not have to do mental math. My advice is to always try to fast longer than shorter. If you know you have to eat an hour earlier the next day cut your eating window short. But at the end of the day if you get 16,15,14,19,17,15,17,16,16,16,16,15,18,12,14,15 as your fasting pattern it’s not gonna kill you or ruin the effects. You’ll find a Rhythm that works and id always advice eating an hour or 30 minutes early if you are very hungry then waiting and being so hungry you over eat. I also recommend breaking your fast with a low calorie but filling snack to suppress the initial binge phase and allow your self to eat for thoughtfully for the rest of the period. At the end of the day though you’ll find what works for you. Use the 2 weeks to learn how your body feels a bad adjust. I quickly went from 16:8 to 23:1/ omad and was very happy for about 9 months and lost the weight I want. Now I eat back on a 16:8-14:10 schedule most days and will go back to a 20:4 for a short stint I see back habits coming back into it.