How do I increase default font size in Reminders under Mavericks?
I've had a look at it and at a glance (with a disassembler) there's no .plist (property list) file that could have anything that it directly would use to alter the size.

The size of the sidebar is inherited from what Apple call "Aqua", which is the default theme for OSX. Although they allow you to over-ride side-bars in most apps, they haven't allowed this in ALL apps, which is perplexing as I have the same issue!

I'd strongly suggest that you drop the resolution of your display. This will generally make the font (and everything else) across the system larger, depending of course what you set it to!

You can do this by:


Click on  (Apple, Top Left)
Click on "System Preferences"
Click on "Displays"


note here that you might see:



This is the system default setting which is generally acceptable with people who are neither nor nor far sighted To change this, carry on to 4 below.. If you don't just close the screen as you would any other screen.


Change the setting shown above to "Scaled", which will present you something similar to:




`Mine is set to the highest possible setting on this MacBook (1440 x 900), so if I click on one setting lower, that is (1344 x 840), the above image would be larger, and as I click on the various ones going down, they get gradually more "zoomed" as to put it.

MAKE SURE YOU MAKE A NOTE OF THE SETTINGS IT WAS ALL INITIALLY ON!

Without unorthodox system "hacks" there is no run of the mill way to change what you need changed sadly.

Hope this helps!

Adrian S