Comparison

CoolGuard vs SleepCall

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

Head to head
About

CoolGuard

This app monitors your phone's temperature, providing real-time heat levels and alerts to prevent performance issues and battery aging. It also functions as a customizable night clock with alarms and displays local weather information.

Highlights
  • Live heat level monitoring
  • Heat trend and log with map
  • Customizable alerts and cooling tips
  • Night clock with sleep mode
  • Multiple alarms with system integration
  • Outdoor weather display
  • Lock screen and Dynamic Island widgets
Features
Read full description

CoolGuard keeps an eye on your phone's heat — and at night, it's the clock on your nightstand. A hot iPhone runs slower, its battery ages faster, and in summer it heats up within moments in the sun or while gaming, navigating, or charging. CoolGuard shows you where your phone stands on a four-level scale (Normal, Slightly Warm, Hot, Critical), warns you in time, and tells you what to do. HEAT MONITORING • Live heat level on the main screen, with a color-coded ring and a quick tip • Heat Trend: 1-hour and 24-hour curves in a banded or clean style — drag your finger to read the details • Heat Log with calendar and map: when and where your phone got hot • Alerts from the level you choose: push notifications, sound alerts, quiet hours • Monitor Mode: background monitoring, with a Live Activity on the Lock Screen and in the Dynamic Island • Cooling tips and a carefully curated selection of active coolers NIGHT CLOCK AND ALARM • Sleep Mode: dark screen with just the clock and the outdoor temperature — three sizes, your choice of color • Alarms: up to 10, repeating daily; on iOS 26 and later they ring through the system alarm, even when your phone is silenced • Landscape view: big clock, swipeable alarm bar, brightness slider • Burn-in protection: slow pixel drift and dimming to keep your display safe • 12- or 24-hour clock, with seconds if you like WEATHER • Outdoor temperature, with today's and tomorrow's highs and lows • Weather face in the ring: the sun and moon travel around it from sunrise to sunset • A warning on dangerously hot days WIDGET • Small: thermometer, weather, battery level, clock • Medium: adds the heat trend curve and the date • Works on the Lock Screen, too BATTERY • Battery Health and cycle count, compared month by month with your phone's heat MORE • 50 languages, Celsius or Fahrenheit • Private by design: no ads, no analytics, no accounts — your Heat Log never leaves your phone • Free — you can support development with a tip Note: iOS doesn't expose exact temperatures to apps — CoolGuard shows Apple's four official thermal levels.

About

SleepCall

Read full description

Choose when to end your bedtime call. SleepCall connects to Apple Shortcuts to schedule your call to end. Sleep log · Statistics Log your bedtime and wake-up time, and set morning reminders for each day of the week. View your sleep calendar, 7-day average, and consecutive and total days of call-timer use. Sleep and actual call duration are not measured automatically. With Screen Time permission, choose one app to block on a daily schedule, with or without PRO. After an 8-second breathing exercise, you may allow 1–60 minutes of temporary access. When it expires, blocking resumes until the daily blocking period ends. Free features • 15-minute, 30-minute and 1-hour timers • Lock Screen and Home Screen widgets, Control Center and Siri • Vibration before the timer ends, cancellation and recovery guidance Choose your own time with PRO (1 minute–12 hours) Set a custom duration or end time, change the time during a timer, or extend it by 30 minutes. PRO is a monthly subscription that renews automatically. The price is shown on the purchase screen. You can cancel through your Apple Account's subscription management. Existing lifetime purchases remain valid and can be restored using Restore Purchases. How it works One call timer uses a shortcut that turns Airplane Mode on and Wi-Fi off. If the end of the call is detected, connectivity may return early; otherwise, within 60 seconds, it turns Airplane Mode off and Wi-Fi on. Results vary by app and device. Use the in-app 10-second test before relying on it. Connect the shortcut before your first timer. Before starting, check that Airplane Mode is off, cellular data is on and Wi-Fi is on. The app cannot read your network settings and does not automatically restore your previous settings. If the shortcut stops, turn Airplane Mode off and turn cellular data and Wi-Fi on in Settings. Email the developer from Settings → Help. Timers and settings stay on this iPhone. We do not collect your contacts, call content or phone numbers. Requires iOS 27.0 or later. Terms of Use: https://getsleepcall.com/en/terms/ Privacy Policy: https://getsleepcall.com/en/privacy/

Screenshots

CoolGuard4 screens
SleepCall4 screens

Verdict

The call

The clearest difference is iOS requirement: CoolGuard at 17.0 against SleepCall's 27.0. On price, update cadence, ads and in-app purchases 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. CoolGuard sells 3 one-off in-app purchases and SleepCall sells 1 in-app purchase, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

CoolGuard ships an update weekly, SleepCall every 5 days. Both last shipped on November 10, 2026.

Scorecard1 real difference · 8 level
CoolGuard versus SleepCall: the parameters behind the verdict, then further details
ParameterCoolGuardSleepCall
PriceFreeFree
Rating4.3 (4 ratings) — better—
Number of ratings4 — better—
Update frequencyWeeklyEvery 5 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree—
DevicesiPhone, iPad — betteriPhone
Requires iOS17.0 — better27.0
Further details — not scored
Size7 MB24 MB
Age rating4+4+
DeveloperNorbert PentekIlwolobongdo

In-app purchases

3 purchases

CoolGuard

One-time3
  • Small tip$0.99
  • Medium tip$2.99
  • Large tip$9.99
1 purchases

SleepCall

Subscriptions1
  • SleepCall PRO Monthly$1.991 Month

Questions

Is CoolGuard free?
CoolGuard is free to download, with in-app purchases available.
Is SleepCall free?
SleepCall is free to download, with in-app purchases available.
Do CoolGuard or SleepCall have ads?
Neither CoolGuard nor SleepCall shows ads.
Which is updated more often, CoolGuard or SleepCall?
CoolGuard ships an update weekly, and SleepCall every 5 days. Most recently, CoolGuard was updated on November 10, 2026 and SleepCall on November 10, 2026.

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