Get Your Book, Make It Free
Suggestion: Release your book as an EPUB rather than a PDF.  PDF has the reputation of being view-able "everywhere", but it's not exactly pleasant to read on anything other than a computer screen or a large tablet.EPUB's, however, can dynamically reflow the text and resize the font to be readable on your phone, your Kindle, your PC, etc. And they're far easier to cleanly convert to other formats (even PDF, if that's your only option) than the reverse direction.