As owner of > 500 purchased apps on Mac App Store and iOS App Store, and careful observation of buying trends at various price points, I'd say $4.99 is the impulse ceiling.
For iOS apps I am familiar with and use regularly, I have paid as much as $49.99; Mac apps, as much as $299.
This app, to me, in its current incarnation and marketing, looks like $4.99 "launch price" and $9.99 tops once it's finished (it doesn't look finished). There are notably (sorry) better editors for less money.
Writeroom $9.99
iA Writer $8.99 (iOS $0.99)
Byword $9.99 (iOS $2.99)
OmmWriter Dāna II $4.99
Perspective:
Pages $19.99
Given the competition and its marketing, I'd recommend undercutting the other guys by as much as 1/2, and discounting your launch pricing further.
// Disclaimer: utterly speculative opinion, YM will V
EDIT: While researching these, I discovered "Marked", and saw it offers GitHub technical markdown preview. I purchased it for $3.99, because I hadn't spent money on coffee today.
I would have to agree with @Terretta. A launch price is probably your best bet while your user base grows, praises and criticisms flow in (along with reviews), a few updates to the program happen and you finally settle on a price that can sustain further development and feed your family.
All of this is moot if $14.99 is indeed your launch price.
For iOS apps I am familiar with and use regularly, I have paid as much as $49.99; Mac apps, as much as $299.
This app, to me, in its current incarnation and marketing, looks like $4.99 "launch price" and $9.99 tops once it's finished (it doesn't look finished). There are notably (sorry) better editors for less money.
Perspective: Given the competition and its marketing, I'd recommend undercutting the other guys by as much as 1/2, and discounting your launch pricing further.// Disclaimer: utterly speculative opinion, YM will V
EDIT: While researching these, I discovered "Marked", and saw it offers GitHub technical markdown preview. I purchased it for $3.99, because I hadn't spent money on coffee today.