Comparison

M System vs PrefixBlock

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

Head to head
About

M System

Features
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Our app is built to help individuals manage their personal schedule and tasks more efficiently, ensuring that they can stay on top of their daily responsibilities and get more done in less time. We take pride in providing our users with a secure and reliable platform to manage their personal tasks, without compromising their privacy or sharing their data with third parties.

About

PrefixBlock

Features
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• 17 languages and 69 countries — block prefixes at home and abroad Chặn Đầu Số identifies and warns you about spam calls and texts by prefix. When a number from a prefix you added calls, the app shows a "Spam" label right on your screen. Other apps only block one number at a time — block this one, they call from the next. Chặn Đầu Số works differently: you block the whole prefix (024899, for example) and the app covers every number starting with it. Spam operations buy numbers in bulk blocks, so blocking by prefix hits them at the source. Key features: • Block calls by landline prefix — 024 (Hanoi), 028 (Ho Chi Minh City) and more • Filter spam SMS from those same prefixes too • Quick-block suggestions for the most common telesales prefixes — one tap • "Warn only" mode — show a label instead of hard-blocking, your choice • Bilingual Vietnamese / English, switch right inside the app Privacy first: • Does NOT read or upload your contacts • NO ads, NO tracking • Your block list stays on your device Free for up to 500,000 numbers. Upgrade to Premium (monthly / yearly / lifetime) to block without limits. Note: iOS handles blocking silently, and it does not block numbers saved in your Contacts. Terms of Use: https://phungdoanh.github.io/term.html Privacy Policy: https://phungdoanh.github.io/privacy_policy.html

Screenshots

M System4 screens
PrefixBlock3 screens

Verdict

The call

The clearest difference is in-app purchases: M System at none against PrefixBlock's 3. M System also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.6). PrefixBlock's advantage is update cadence (every 3 days vs weekly). On price and ads 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. PrefixBlock sells 3 in-app purchases, starting at $0.99 per month. M System asks for nothing beyond the download.

UpkeepUpdate frequency

M System ships an update weekly, PrefixBlock every 3 days. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

Scorecard4 real differences · 2 level
M System versus PrefixBlock: the parameters behind the verdict, then further details
ParameterM SystemPrefixBlock
PriceFreeFree
Update frequencyWeeklyEvery 3 days — better
AdsNoNo
In-app purchasesNo — betterYes
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.0 — better17.6
Further details — not scored
Size206 MB4 MB
Age rating4+4+
DeveloperVu Pham AnhPhung Doanh

In-app purchases

None

M System

No in-app purchases

3 purchases

PrefixBlock

Subscriptions2
  • Chặn đầu số pro tháng$0.991 Month
  • Chặn đầu số pro năm$4.991 Year
One-time1
  • Chặn đầu số trọn đời$9.99

Questions

Is M System free?
M System is free to download, with no in-app purchases.
Is PrefixBlock free?
PrefixBlock is free to download, with in-app purchases available.
Do M System or PrefixBlock have ads?
Neither M System nor PrefixBlock shows ads.
Which is updated more often, M System or PrefixBlock?
M System ships an update weekly, and PrefixBlock every 3 days. Most recently, M System was updated on October 24, 2026 and PrefixBlock on October 25, 2026.

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