Redditlater - An app that lets you schedule a post to Reddit
Subreddit Stats - Statistics for every subreddit.
The Reddit Marketing Code - A guide to cracking the Reddit marketing code
FrontPageMetrics - Daily updated statistics for every subreddit on Reddit. Top subreddits, new subreddits by date, all subreddits, trending subreddits, plus more Reddit stats
Serializer.io - A compact news reader for HN, Product Hunt and more
Redective - Find information about Reddit users