Iline Developer
This is Ryusei__46 here.
Lately, I've been writing articles while working on personal projects, which has been quite demanding, but I'm doing my best.
Now, I'd like to share a method for researching other personal development services and apps—whether you're brainstorming ideas, conducting market research, or simply looking for inspiration for your own current project. These insights can be incredibly useful.
Depending on your reason for personal development, understanding the demand and market size of your target genre is crucial.
Check the release announcement site for individual developers
There are several websites where individual developers can announce their created web services and smartphone apps.
Applishowは、WEBサービスやアプリを紹介しているサイトです。アプリ開発者は、すぐにアプリを登録して自分のアプリを紹介することができます。カテゴリ分けされていますので、テーマやジャンルが決まっている状態で探す際や類似・競合サービスを探したりする際に便利です。
ツクログは、個人で制作したWebサービス、スマホアプリ、ゲーム、LINEスタンプ、イラストなどをPRできるポートフォリオサービスです。
Additionally, while the following services are international, they're used by individual developers worldwide. The scale really is different.
Product Hunt is a curation of the best new products, every day. Discover the latest mobile apps, websites, and technology products that everyone's talking about.
Connect with developers sharing the strategies and revenue numbers behind their companies and side projects.
Find individual developers on X (formerly Twitter)
Many individual developers regularly share their development progress and daily insights, so try searching Twitter's keyword search box with terms like "individual development" - you'll find numerous relevant accounts.
Additionally, when you discover such accounts, it's good to check their followings and followers too, as individual developers often form connected networks.
Find individual developers on Qiita, Zenn, and note
Both Qiita and Zenn are platforms where engineers and individual developers frequently find valuable content, with technical insights related to programming being regularly posted.
Among these, there are many articles that explain and showcase personal development projects while also discussing their technical aspects. If you perform a keyword search for "personal development" on either site, you'll find numerous relevant results.
個人開発に関する情報が集まっています。現在3533件の記事があります。また1200人のユーザーが個人開発タグをフォローしています。
By the way, Zenn itself was also personally developed by Catnose. While note isn't exclusively a technical blogging service, many developers share their personal development experiences there.
Moreover, even beyond these blogging platforms, there are many individuals—like myself—who operate their own technical media sites by renting servers and custom domains. Simply searching for terms like "personal development blog" or "app development blog" in Google should yield numerous results.
Bonus: Articles introducing individual developers
この記事について 後学のために、利益を上げている個人開発者とその代表的アプリをまとめました。 選定基準 個人開発者もしくは法人化して3年以内の元個人開発者であること。 収益を出していること。もしくは出していると思われること。(目安：16万/月以上) 個人開発で達成でき...
Bonus: Checking traffic statistics for personal web services
If we could even roughly estimate the monthly traffic for personally developed web services that are actually in operation, it would allow us to forecast market size - which would be extremely useful for your own personal development projects.
While these are only estimates, you can use "similarweb" to determine a service's monthly number of visitors.
Similarweb is an AI-powered digital data company providing real-time market intelligence, competitive insights, and consumer trends to accelerate business growth.
If you are using a Chromium-based browser, there is an extension available—using this would be more convenient. The browser supports Edge, Chrome, Opera, and Firefox.
Extension | Similarweb
After adding the extension, you'll see the "similarweb" icon. Clicking it will display the following popup overlay on the right side of the screen.
The data displayed is from "Zenn." The "Monthly Visits" section, highlighted in red, shows the number of monthly visitors. Here it reads "10.1M," indicating an estimated 10 million monthly visitors - impressive!
If calculated by page views, we might estimate "10 million visitors × 1.5 = approximately 15 million page views."
However, since this is a newly launched niche site with very little data, "similarweb" doesn't display any information. It appears that only after gaining some traffic and increasing visibility will data start accumulating in "similarweb."
Conclusion
This time, I've introduced all the sites I typically check when starting a new personal development project. These serve as crucial indicators of whether your service will succeed, so I highly recommend taking them into account.