Comparison

POLARIE U vs PurpleTracker

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

Head to head
About

POLARIE U

This app enhances night sky photography by controlling a star tracker. It offers various rotation speeds, camera shutter control, and advanced imaging modes for creating stunning time-lapses and HDR images of celestial objects.

Highlights
  • Variable rotation speeds
  • Custom rotation speed settings
  • Camera shutter control
  • Shoot-move-shoot function
  • Accurate star tracking
  • Bracketed imaging for HDR
  • Night vision light
Features
Read full description

The POLARIE U app is an app dedicated to the POLARIE U star tracker offered by Vixen. Shooting night skies is easy if only the POLARIE U. With the use of this app, however, you will enjoy creating a time-lapse movie of a higher level. Major features - Various speeds of rotations. (10x of the sidereal tracking rate at the maximum.) - The rotation speeds are available to set in the Custom Mode. - Control a camera shutter with an optionally available shutter release cable. - The motion of a POLARIE U can be linked with the shutter control (Shoot-move-shoot function). - Tracks the motion of stars accurately and the stars appear no trails in long exposures. - The bracketed imaging mode is available. It is effective in capturing fainter celestial objects such as diffuse and emission nebulae and it allows for creating HDR images using a stack of different exposures. A photo with a dynamic range wider than by a single shot will be a result. - The night vision light is available to use with either red light color or incandescent light color. - The screen colors are available for daytime use and nighttime use.

About

PurpleTracker

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PurpleTracker is a smart App designed for pet owners. It's bulit-in presice GPS to track the pet's location in real time, and the GPS electronic fence function notify the owner when the pet crosses the boundary to ensure the pet's safety. Moreover, the APP also monitor the pet's exercise and health data to help owner know the pet's daily activities and health status.

Screenshots

POLARIE U3 screens
PurpleTracker4 screens

Verdict

The call

The clearest difference is update cadence: POLARIE U at every 2 months against PurpleTracker's every 4 months. POLARIE U also leads on iOS requirement (11.0 vs 14.0). On price, ads, in-app purchases and device support 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

POLARIE U ships an update every 2 months, PurpleTracker every 4 months. The most recent releases landed on October 24, 2026 and October 7, 2026 respectively.

Scorecard2 real differences · 8 level
POLARIE U versus PurpleTracker: the parameters behind the verdict, then further details
ParameterPOLARIE UPurpleTracker
PriceFreeFree
Rating4.0 (1 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings1 — better—
Update frequencyEvery 2 months — betterEvery 4 months
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS11.0 — better14.0
Further details — not scored
Size5 MB79 MB
Age rating4+17+
DeveloperVixen Co.,Ltd.HUIZHOU REDBOX ELECTRONICS CO,.LTD

In-app purchases

None

POLARIE U

No in-app purchases

None

PurpleTracker

No in-app purchases

Questions

Is POLARIE U free?
POLARIE U is free to download, with no in-app purchases.
Is PurpleTracker free?
PurpleTracker is free to download, with no in-app purchases.
Do POLARIE U or PurpleTracker have ads?
Neither POLARIE U nor PurpleTracker shows ads.
Which is updated more often, POLARIE U or PurpleTracker?
POLARIE U ships an update every 2 months, and PurpleTracker every 4 months. Most recently, POLARIE U was updated on October 24, 2026 and PurpleTracker on October 7, 2026.

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