Apple's new font in iOS7 can be a little challenging to read if your eyesight is not perfect or its been a long day.
You can increase the font size in Settings under General. If that increase is not enough Apple has a solution for you.
Larger Dynamic Type
In Settings go to General then Accessibility and you can activate the Larger Dynamic Type. You will be pleasantly surprised how much easier it is to read once you activate this option.
Here is a link in iMore's Guides and How To section to help you through the steps:
http://forums.imore.com/guides-how-articles/288220-guide-activating-larger-dynamic-type.html
You can increase the font size in Settings under General. If that increase is not enough Apple has a solution for you.
Larger Dynamic Type
In Settings go to General then Accessibility and you can activate the Larger Dynamic Type. You will be pleasantly surprised how much easier it is to read once you activate this option.
Here is a link in iMore's Guides and How To section to help you through the steps:
http://forums.imore.com/guides-how-articles/288220-guide-activating-larger-dynamic-type.html