TrialDiary: SaaS Tool Evaluation Journal & Buy/Kill Decision Engine for Indie Builders

The Problem

Solo founders on r/indiehackers and HN regularly start free trials of 5-10 tools simultaneously, lose track of evaluation criteria mid-trial, and either auto-convert to paid plans they barely use or forget to cancel before billing. TrialDiary lets builders log tools under evaluation, attach structured notes per session, set kill criteria upfront, and receive a final 'buy or kill' verdict prompt 48 hours before each trial expires — turning chaotic tool sprawl into a deliberate decision ledger.

Target Audience

Solo SaaS founders and indie builders managing 3-15 active SaaS trials at any given time

Monetization Angle

$6/mo flat subscription or one-time $29 purchase; upsell a shared team workspace at $15/mo

Recommended Tech Stack

Why Now

The explosion of AI-native SaaS tools in 2024-2025 means indie builders are trialing more tools than ever before, making trial fatigue and accidental billing a daily pain point.

MVP Scope

A simple form to log a tool name, trial end date, kill criteria, and session notes — with an email reminder 48 hours before expiry.

AI Angle

AI can analyze session notes across all trials and suggest a ranked buy/kill recommendation based on stated goals, actual usage frequency, and price-to-value signals.

Primary Risk

The audience may prefer a spreadsheet and resist paying for a lightweight logger unless the 'verdict prompt' and benchmark comparison features deliver genuine decision clarity.

Validation Checklist

• Post 'How do you track SaaS trials before they auto-bill?' on r/indiehackers and measure response volume and format of current workarounds
• Build a no-code Notion template version first and share it free — if 200+ people clone it in a week, build the app
• DM 20 active indie hackers who post about their tool stacks and ask if they've ever been accidentally billed by a forgotten trial
• Launch a $29 lifetime deal on Gumroad with a waitlist page; validate with 10 pre-sales before writing a line of code

Who Would Pay For This

Likely buyers are founders, operators, and small teams with a recurring business process. Start with Solo SaaS founders and indie builders managing 3-15 active SaaS trials at any given time and validate whether this can replace a spreadsheet, manual review, or consultant workflow.

First 10 Users

Find the first 10 users by searching for recent complaints around "SaaS indie hacker" in Reddit, developer communities, GitHub issues, and niche Slack or Discord groups. Offer a concierge version first: manually solve the workflow for a few users, then automate only the repeated steps.

Idea Playbooks

This opportunity also appears in curated IdeaGenius playbooks for builders comparing adjacent markets.

More Developer Search Paths

Why This Idea Has Legs

• Sourced from real discussions and complaints across Reddit and social media
• Cross-checked against recurring demand signals in the IdeaGenius archive
• Difficulty rated Easy — buildable by a solo developer or small team
• Clear monetization path from day one

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