Comparison

Stack｜自己投資アプリ vs Zentime

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head

Set limits. Auto-lock apps

Free

📊 Productivity

No ratingsView app →

About

Stack｜自己投資アプリ

Features

Read full description

自己投資にハマるための今ままでにないプラットフォーム

About

Zentime

This app helps you regain focus by automatically locking applications after a set usage time. It enforces limits to prevent mindless scrolling and time-wasting, promoting calmer, more productive phone usage.

Highlights

Automatic app locking
Customizable usage timers
Enforced app limits
Reduces mindless scrolling
Promotes focused time

Read full description

Zentime is a simple app blocker for calmer, more focused time on your phone. Choose how long you want to use an app before you open it—when the timer ends, Zentime locks the app automatically. Because the block is enforced—not just a reminder—Zentime helps you avoid mindless scrolling and stop wasting time. We hope Zentime makes your day a little better. Privacy Policy: https://tinylab-apps.web.app/zentime/privacy Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula

Screenshots

Stack｜自己投資アプリ4 screens

Zentime4 screens

Verdict

The call

The clearest difference is in-app purchases: Stack｜自己投資アプリ at none against Zentime's 7. Stack｜自己投資アプリ also leads on ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Zentime sells 6 in-app purchases, starting at $3.99 per month. Stack｜自己投資アプリ asks for nothing beyond the download.

UpkeepUpdate frequency

Stack｜自己投資アプリ ships an update every 10 days, Zentime weekly. The most recent releases landed on September 28, 2026 and October 1, 2026 respectively.

Scorecard2 real differences · 6 level

Stack｜自己投資アプリ versus Zentime: the parameters behind the verdict, then further details
Parameter	Stack｜自己投資アプリ	Zentime
Price	Free	Free
Positive reviews	—	88.2% of reviews
Update frequency	Every 10 days	Weekly — better
Ads	No — better	Yes
In-app purchases	No — better	Yes
Monetization	—	Free with in-app purchases
Devices	iPhone, iPad — better	iPhone
Requires iOS	17.0 — better	18.0
Further details — not scored
Size	41 MB	72 MB
Age rating	17+	4+
Developer	Nagato Kadoya	Ryunosuke Nagase

In-app purchases

None

Stack｜自己投資アプリ

No in-app purchases

6 purchases

Zentime

Subscriptions4

Zentime Pro2 variants$3.991 Month
Zentime Pro$5.991 Month
Zentime Pro7 Days trial$19.991 Year

Show 1 more

Zentime Pro7 Days trial$29.991 Year

One-time2

Zentime Pro$59.99
Zentime Pro$99.99

Questions

Is Stack｜自己投資アプリ free?

Stack｜自己投資アプリ is free to download, with no in-app purchases.

Is Zentime free?

Zentime is free to download, with in-app purchases available.

Do Stack｜自己投資アプリ or Zentime have ads?

Zentime shows ads; Stack｜自己投資アプリ does not.

Which is updated more often, Stack｜自己投資アプリ or Zentime?

Stack｜自己投資アプリ ships an update every 10 days, and Zentime weekly. Most recently, Stack｜自己投資アプリ was updated on September 28, 2026 and Zentime on October 1, 2026.