Record vaping counts, personal check-ins and self-selected goals in a mobile diary.
Record vaping counts, personal check-ins and self-selected goals in a mobile diary. The July 19, 2026 original article identifies Matheus Mello as solo founder at Quantivo AI and presents his own subscription-app portfolio. The current Google Play listing names Matheus Mello and links the official Puff Zero website. Exact current employee and contractor counts are not established by the dated solo-founder statement.
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Source-linked product facts, followed by MRRTrace analysis of the customer problem, workflow, trade-offs and questions to test.
The official product offers a tap counter, personal check-ins and a history dashboard. Editorial interpretation: a prospective customer wants a record they can maintain during ordinary daily activity without opening a complicated form each time. Begin an interview with the last attempt to record this behavior, the situation in which an entry was missed and what happened when the person returned. A useful design question is whether the user can recover a mistaken or omitted entry without feeling that the entire record has become useless. The research task should evaluate recording and retrieval, while leaving clinical benefit outside the conclusion. A prototype can use fictional events and a chosen reminder schedule to observe entry effort without requiring a participant to change behavior.
Editorial analysis: measure whether people can enter a sample event, correct its timestamp and later explain the resulting daily total. Compare the displayed history with the fictional inputs so that arithmetic and navigation are tested separately from self-report completeness. Repeated opening or a long streak does not establish a health outcome. For commercial validation, observe which report or convenience motivates a paid upgrade, whether it remains useful after several weeks and how cancellation affects the renewal cohort. With three reported paying subscribers, a single renewal can substantially change the snapshot. Acquisition spending, store fees, inference usage and support time would be needed to understand contribution margin. Ask whether a simpler counter and export provide most of the desired value before expanding the conversational feature. These are proposed usability and business checks; this profile reports no completed trial, measured behavior change or medical result.
Observed channels and entry points; their performance is not inferred.
The official website links the exact Android package, whose store listing links back to puffzero.app. The original income report does not give product-specific acquisition spending, sources or attribution, so no channel performance claim is inferred.
EvidenceA MRRTrace reading of public product material. Trade-offs and questions are editorial analysis.
The Puff Zero row reports $13 in the MRR column and three paying subscribers. The article gives a dollar sign without naming the currency; current US-store pricing is not evidence for the historical revenue currency. The ten-app portfolio's MRR and 28-day collected total are separate figures and are not assigned to this app. Fees, refunds, taxes, costs and profit are unreported. No independent payment audit.
Matheus Mello, original first-person portfolio disclosure on SoleOSOfficial website checked October 20, 2026 lists US-store prices of $4.99/week, $9.99/month or $49.99/year, with no free trial. Regional prices can differ. This current offer does not establish the July plan mix.
The source page may change its prices, limits, or offer after the recorded check date.
Study whether a quick personal logging task and understandable history support voluntary use and subscription renewal.
These are MRRTrace observations, not statements by the founder or proof of a repeatable outcome.