Scientific Calculator Plus 991 subscription: cost, reviews, how to cancel

• App Store rating4.7★ from 12,520 ratings
• Cheapest subscription$1.99 per month
• Reviews mentioning billing, last 12 months3 of 98 reviews

On this page: what it costs, how to cancel, what reviewers say.

What the data says

No label applies: the numbers below sit inside the normal range for apps of this size.

What Scientific Calculator Plus 991 costs

Download: Free. Subscriptions start at $1.99 per month.

• Calculator month subscriptionRenews every month, no trial$1.99
• Calculator yearly subscriptionRenews every year, no trial$3.99

How to cancel Scientific Calculator Plus 991

1. Open Settings on your iPhone and tap your name at the top.
2. Tap Subscriptions.
3. Select Scientific Calculator Plus 991 (listed under a plan name such as Calculator month subscription).
4. Tap Cancel Subscription and confirm. You keep access until the end of the paid period.

If the app is not in that list, it was not billed through Apple. Cancel it with the developer instead: support page or website.

Charged after cancelling or during a trial? Request a refund at reportaproblem.apple.com within 90 days.

What reviewers say

Reported bugs

Keyboard input stops working after switching screens; Incorrect calculation results for certain operations; App crashes on some devices after recent update.

Recent one-star reviews

adsi’m seeing half naked girls as ads like wtf

ДробиОтветы показывает в дробях, нет возможности вывести в научном формате или десятичных дробях

incorrectwhen typed in for example -2^2 it gives -4 when in reality you cannot get a negative when something is squared

Recent five-star reviews

HervorragendMit Abstand der beste Taschenrechner für die Hosentasche! Ich nutze die App seit 3 Jahren gerne und sie ist nach jedem Update sogar noch besser geworden. Die Vollversion lohnt sich, der Entwickler gibt sich wirklich Mühe und das merkt man auch. Ein Muss für die Baustelle oder im Ingenieursstudium.…

Fantastic app! 😊This calculator is really well built. It’s easy and distinctive to press keys I don’t usually write reviews, but this one deserves all the praise! Absolutely fantastic! 😄😄

Simply put, the best calculator I’ve ever had!I was always fascinated by what calculators could offer, and even though I had in the past some quite capable ones, NCalc is just the best of them all, the simplest and most intuitive to use, and the one with the most attention to detail on its user interface I’ve seen so far!

About the developer

Tran Duy has published on the App Store since Apr 3, 2019: 2 app(s), 0 of them no longer in the store.

• Graphing Calculator 84: Calc844.6★

Alternatives to Scientific Calculator Plus 991

Also similar: Scientific Calculator fx-991 (4.6★), GeoGebra Calculator Suite (4.3★), GeoGebra Graphing Calculator (4.3★), Taculator 84 Graphing Calc (4.5★), GeoGebra 3D Calculator (4.0★), Desmos Scientific Calculator (4.3★)

Questions people ask

How much does Scientific Calculator Plus 991 cost?

Download: Free. Subscriptions start at $1.99 per month.

How do I cancel Scientific Calculator Plus 991?

On your iPhone open Settings, tap your name, tap Subscriptions, select Scientific Calculator Plus 991 and tap Cancel Subscription. You keep access until the end of the paid period.

Does Scientific Calculator Plus 991 have a free trial?

No plan lists a free trial in the US App Store.

Is NCalc Scientific Calculator + free to use?

The application is available for free download and use, but it does contain in-app purchases. This means that while the core functionality is accessible, certain advanced features or content may require a purchase to unlock.

Scientific Calculator Plus 991 in one paragraph

Scientific Calculator Plus 991 by Tran Duy is a Education app for iPhone. Download: Free. Subscriptions start at $1.99 per month across 2 plan(s). App Store rating 4.7 from 12,520 ratings. 3 of 98 reviews in the last 12 months mention charges, subscriptions, refunds or cancelling (3%). The developer has 2 app(s) on the App Store, 0 no longer listed. Cancel through Settings › Subscriptions on the iPhone. Data verified Oct 23, 2026 by AppsLupa.

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