I think it depends on how you use it. I look at app blogs for very specific things: roadmap posts, changelogs, bug reports filed and fixed, etc. I like knowin

I think it depends on how you use it. I look at app blogs for very specific things: roadmap posts, changelogs, bug reports filed and fixed, etc. I like knowing that the devs of various apps I use are not only active, but willing to make changes public. If you already have a user forum, you probably don't need a blog; assuming you have one specific pinned news thread that you keep up to date. If you don't you're misusing your forum. If you can include a series of user guides for various topics related to your app, or prove (preferably with visual examples) how your app provides a solution to some issue or whatnot, then your blog will have value. If you already have a wiki or a forum, you probably don't need a blog. If you think you have something worth sharing that's important to others outside the specific niche your app fills but tangential to it, go for it; but you'd probably be better off on Facebook or Twitter.