Opportunity 1607 · Calendar · Mobile app · free in full
Calendar app with reliable data persistence and backups
Users need calendar apps with reliable data persistence and backup recovery options to prevent catastrophic loss of event history
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70 mentions2 sourcesRISINGFRAGMENTEDfirst seen 2022-09-05latest 2026-09-09
Evidence strength: multiple-source pattern. Mentions are posts or reviews, not verified unique customers. Scores rank signals; they do not predict business success.
Disappointed in the End — I’ve used this app for years. It has been great. Very user friendly. But it has one fatal flaw. This calendar will randomly clear all your events, with no way to retrieve them. I had backup turned on but nothing appeared in my other…Simple Calendar - SimpleCal · ★☆☆☆☆ · App Store review · 2026-05-25 · 1 engagement
Deleted everything — I’ve used this app for years and had my whole life in it to keep organised and today everything was wiped. All previous and future events gone. I’ll be switching to another app because I can’t trust this one with important dates. A paper…Calendar · ★☆☆☆☆ · App Store review · 2026-08-18
Timetree deleted everything! — My entire calendar was randomly wiped out one day! I needed those dates stored on the calendar, they were incredibly important medical appointments and legal due dates and correspondence, and I opened the app one day to find…TimeTree: Shared Calendar · ★☆☆☆☆ · App Store review · 2026-07-22
Pro accounts can have a build memo written for any opportunity: verdict, wedge, a two-weekend MVP spec, pricing and acquisition hypotheses, observations cited to reviews and hypotheses clearly labeled.
Demand blends volume, growth, how many independent sources agree. Supply gap measures how often complainers name an existing tool and how hard they complain about it; ad-spend and search-cost signals are not yet part of it. Scores shrink toward the middle when a cluster rests on few mentions. How scoring works.