Comparison

Alfredo Backer vs Circle & Sphere

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

Head to head
About

Alfredo Backer

Features
Read full description

Este é o aplicativo do Externato Alfredo Backer Desenvolvido para apresentar aos alunos, pais e responsáveis diversas funcionalidades, tais como: • As avaliações e faltas do ano ou semestre atual e passados, com envio de notificações e push quando as avaliações forem liberadas ou alteradas pela Instituição ou pelo professor. • Consulta financeira das parcelas atuais e vencidas, com a possibilidade de cópia da linha digitável para pagamento do boleto no aplicativo do banco de sua preferência. • Consulta do horário, sala e professor das disciplinas matriculadas, com possibilidade de adicionar lembrete do dia da aula. Envio de notificação caso tenha alteração de horário e sala. • Consulta Pedagógica com a possibilidade de filtrar por período da ocorrência. Envio de notificação no caso de nova informação pedagógica (ocorrências). • Consulta de Eventos com a possibilidade de adicionar lembretes de eventos futuros.

About

Circle & Sphere

Instantly solve geometry problems for homework and exams. Calculate circle and sphere properties with step-by-step solutions. Access learning videos and manage your calculations.

Highlights
  • Circle calculations (radius, diameter, circumference, area)
  • Sphere calculations (surface area, volume)
  • Circular sector calculations
  • Step-by-step solutions
  • Learning videos
  • Solution management
Features
Read full description

Do your homework instantly. Prepare for exams without stress. Free, complete step-by-step solutions. Enter your values and calculate: - Circle: radius, diameter, circumference and area - Sphere: surface area and volume - Circular sector: arc length and central angle HOW IT WORKS Enter your values in the correct fields and get started. You receive the solution instantly and can share it with friends or classmates. YOUR PERSONAL DATA We don’t need it. Only anonymized data is collected, for example: - which features are used - how many solutions are generated This helps us improve. We cannot identify you. COSTS Everything is free to use. 24/7 access to your solutions. All solution steps always remain complete. If you need many solutions in a short time, various purchase options are available. EXTRAS - Overview of all measures - all length units - curated learning videos - feedback for incorrect inputs - manage your own solutions - app introduction CONTACT Questions and feedback via Discord or directly in the app review.

Screenshots

Alfredo Backer4 screens
Circle & Sphere4 screens

Verdict

The call

The clearest difference is in-app purchases: Alfredo Backer at none against Circle & Sphere's 8. Circle & Sphere's advantage is update cadence (every 3 weeks vs every 8 months). On price, ads, 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. Circle & Sphere sells 8 one-off in-app purchases. Alfredo Backer asks for nothing beyond the download.

UpkeepUpdate frequency

Alfredo Backer ships an update every 8 months, Circle & Sphere every 3 weeks. The most recent releases landed on November 2, 2026 and November 3, 2026 respectively.

Scorecard2 real differences · 8 level
Alfredo Backer versus Circle & Sphere: the parameters behind the verdict, then further details
ParameterAlfredo BackerCircle & Sphere
PriceFreeFree
Rating—4.0 (4 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—4 — better
Update frequencyEvery 8 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.015.0 — better
Further details — not scored
Size55 MB180 MB
Age rating4+4+
DeveloperExternato Alfredo Backer LtdaGlindemann, Sennoun, Langer GbR

In-app purchases

None

Alfredo Backer

No in-app purchases

8 purchases

Circle & Sphere

One-time8
  • +30 User Tokens$0.29
  • +1 Convenience Token / 6h, max. +2$0.59
  • +2 Convenience Tokens / 6h, max. +4$0.99
Show 5 more
  • +150 User Tokens$0.99
  • +300 User Tokens$1.49
  • +4 Convenience Tokens / 6h, max. +8$1.59
  • Remove Ads$2.99
  • Lifetime Access$2.99

Questions

Is Alfredo Backer free?
Alfredo Backer is free to download, with no in-app purchases.
Is Circle & Sphere free?
Circle & Sphere is free to download, with in-app purchases available.
Do Alfredo Backer or Circle & Sphere have ads?
Neither Alfredo Backer nor Circle & Sphere shows ads.
Which is updated more often, Alfredo Backer or Circle & Sphere?
Alfredo Backer ships an update every 8 months, and Circle & Sphere every 3 weeks. Most recently, Alfredo Backer was updated on November 2, 2026 and Circle & Sphere on November 3, 2026.

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