Blog Posts

Monthly report summarizing November 2025 side income (app development) and investment performance (Rakuten Securities & Defined Contribution Pension). Sharing revenue highlights, investment results, total assets, reflections, and future plans.

An indie developer with 30-40K MAU shares lessons learned from failures, how they improved subscription revenue by 2.5x, and practical RevenueCat implementation guide.

Starting a side business makes time management challenging. Learn 5 sustainable strategies I discovered after failing by working until midnight and affecting my main job.

In 2021, my app revenue reached approximately ¥650,000, requiring my first tax return filing. Choosing blue-form filing, using Money Forward for business registration, and dealing with Google's address disclosure requirement by getting a virtual office. Essential tax and expense management knowledge for indie developers.

My journey expanding iOS success to Android and rebuilding with Flutter. Sharing revenue fluctuations and lessons learned from cross-platform development.

Eight months after my first app rejection, a spark of inspiration on the couch led to my second app. Daily coding at Komeda Coffee, multiple rejections, and the emotional moment of earning my first ¥1. The journey from ¥0 to ¥5,000/month and receiving the 'certificate of indie developer' at ¥8,000.

May 2018, my first app was rejected by Apple review. Guideline 4.2.2 labeled it 'minimal value.' My mind went blank. Two months of isolation and the lessons learned from that failure.

A father of two's journey toward FIRE while balancing parenting, work, and side projects. Tena's path to financial independence.