Name a market. See who is failing it.
Type an industry, pick a country and a platform. We search 45,000 real complaints for what people cannot do, group them into problems worth solving, and hand you a build prompt carrying their own words.
Takes about 30 seconds · No signup required
Reading complaints from
From a stranger’s bad review to your first commit
Four steps, no model guessing in any of them. Every number you see traces back to a row you can open and read.
The full platform
Everything you need in one platform
Twelve sources, 45,000 complaints and twenty tools to find, check and price your next product.
Re-keying every supplier invoice by hand
Asana · Google Tasks
“Spend went from $100 to $1,600/mo”
Hacker News · Cursor
Payouts held 14 days · 3 invoices/mo cap
Market intelligence
Turn negative feedback into product ideas
69 niches, mapped
Category browser
10 hubs · 69 categories
Complaint reports per category
Lifestyle
統一發票兌獎
Complaints
35
1–2 star
28
Avg rating
1.5★
Sources
1
“更新之後直接英文版，是因為我手機是英文介面嗎？ 找不到更改語文的地方～ 直接去APP store, 沒有英文APP的選擇～ 如果有而我找不到，證明不是方便使用的介面😐”
269 companies tracked
- Verified revenue where the source publishes it
- Named competitors and the gap their reviewers describe
- Y Combinator, Product Hunt, Stripe and marketplace listings
Every claim shows its receipts
Evidence
Invoicing built for trades, not for spreadsheets
“I spend the first three days of every month copying numbers off PDFs.”
“No way to import supplier invoices without re-keying every line.”
“Hiring a VA to enter invoice data into QuickBooks weekly.”
+ 12 more, across 4 platforms
Free tools
Twenty calculators, no email required
MRR Calculator
Turn your plan mix into MRR, ARR and average revenue per account.
Churn Rate Calculator
Customer churn, revenue churn, and what they imply about lifetime.
LTV Calculator
Lifetime value, gross-margin adjusted, with the LTV:CAC ratio.
CAC Calculator
Blended and paid-only CAC, plus payback period.
Rule of 40 Calculator
Growth plus margin — the single number investors screen on.
CAC Payback Calculator
How long until a new customer has paid for themselves.
SaaS Metrics Dashboard
Every core SaaS metric from five inputs, in one place.
ARR Growth Calculator
Project ARR forward and find your milestone dates.
Straight from the sources
These are the complaints we read
Real, verbatim, and public. Every one is attributed to where it was published and the product it is about — these are not customer testimonials.
“Invoices are STILL defaulting to another country. When customers try to pay the incorrect invoice, they end up in a never ending loop.”
“They allow them to hold onto your first payment for 14 business days. As somebody that's in the trades usually the payment is for materials.”
“I'm already on the $6.99 a month plan which only allows me 3 invoices per month which is pretty bad.”
“There is no database available in this app that lists available repairs or products. It would ALL have to be custom created by the user.”
“The my tasks section does not keep the same sorting/filtering that I have in the desktop view.”
“My free trial ended today, and I was suddenly locked out of my main calendar with a message about custom fields, which I did not use.”
“I am the administrator, and nothing available to me on the site, the app, or the desktop client is taking me to where I need to go.”
“My usage went from a steady ~$60-100/month to $500+ in a few days, projecting ~$1,600/month. Support told me this was expected.”
“I've used it for 10+ years with 30-40 lists. After switching to iPhone I've been extremely frustrated by how limited the iOS version is.”
“They don't have any back end support. Which means if you have a problem they have no way to fix it.”
Categories
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Get startedKnow it's worth building. Before you build it.
Start with a problem somebody already has, and the evidence that proves it.