Who makes Grumbl, and why

The problem

Most people who want to build an app start by guessing. The guess gets a landing page, a few ads, maybe a prototype, and then it turns out nobody had that problem. Meanwhile the people who do have a problem have already written it down: in a subreddit at 2 am, in a 1-star review, under a YouTube tutorial that didn’t help. Reading all of that by hand takes days, and you still end up with a pile of browser tabs instead of a ranked list.

Grumbl does the reading. You give it a niche, it collects what people complain about in public, groups the complaints by the problem they describe, and ranks the groups by how many different people are stuck, how strongly they say it, and whether anything already fixes it. Every group opens into the posts behind it, with links.

How a scan works

A quick scan reads about 500 posts and reviews from the sources you pick (Reddit, App Store, Google Play, YouTube, TikTok, Instagram). Off-topic items are dropped. An AI model extracts the complaint in each remaining post as a short statement, those statements are grouped by meaning, and each group is scored. The one-paragraph summaries you read are AI-drafted and labelled; the quotes, counts, dates and links are not touched. On 26 Oct 2026 the scan for “budgeting app” read 120 items, kept 70, extracted 76 complaints and ranked 12 opportunities. It cost 5 credits. The method, step by step, is on the features page.

What Grumbl never does

• It never shows who wrote a post. Author handles are replaced by a hash when a post arrives.
• It never reads private groups, direct messages or anything behind a login.
• It never contacts the people whose posts it reads, and the terms forbid you from using it to do so.
• It never invents a quote. If a summary looks wrong, the linked posts are the check.

The name

Grumbl started as a working project called PainMap. The name changed in October 2026; the product is the same.

Changelog

Company details and the support address are on the contact page.