Dialing Code vs Operational Amplifiers Pro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Dialing Code
Access a comprehensive list of international dialing codes for 250 countries. Easily search for country prefixes, view country maps, and save your favorite codes. Share country information effortlessly.
- 250 country prefixes
- Search by country or prefix
- Country information with map
- Personal favorites list
- Share country information
- Retina graphics
- Easy to use
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Find an international dialing code in seconds. Dialing Code helps you look up the calling prefix for a country or territory, whether you’re planning a trip, contacting someone abroad, or checking an unfamiliar international prefix. Search by country name, dialing code, or ISO code. Browse by continent, then open a country to see its flag, calling prefix, location on the map, and local time. Save the places you use most often to Favorites, or share a country and its prefix with someone else. FEATURES • Browse 249 country and territory entries • Search by name, dialing prefix, or ISO code • Filter the list by continent • View flags, country details, and map locations • Check the selected location’s local time • Save and manage favorite countries • Share a country and its dialing code Dialing Code is a reference for international calling prefixes. It does not identify callers or determine the location of a phone number.
Operational Amplifiers Pro
This app provides interactive calculators and reference information for designing and analyzing op-amp circuits. It offers step-by-step explanations and technical data on popular op-amp series, aiding students and engineers in circuit development and prototyping.
- Interactive op-amp circuit calculators
- Step-by-step explanations and formulas
- Reference data on op-amps and comparators
- Support for 14 languages
- Light and dark mode
- Advanced calculators and circuit guides (Pro)
- Full-text search (Pro)
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Operational Amplifiers Pro is your essential tool for designing and analyzing circuits using op-amps. Whether you're a student, electronics enthusiast, or experienced engineer, this app helps you create, calculate, and understand a wide variety of op-amp–based circuits with ease. Use it as a practical reference when developing projects, building prototypes, or studying amplifier configurations. The app also includes technical data on popular operational amplifier and comparator series — making it a handy guide for both design and selection. Available in 14 Languages: • English, French, German, Indonesian, Italian, Japanese, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Turkish, Ukrainian, and Vietnamese — study in your native language! Key Features: • Interactive calculators for common op-amp circuits • Step-by-step explanations and formulas • Reference info on op-amps and comparators • Ideal for learning, prototyping, or quick checks • Light and dark mode support Pro Version Includes: • Advanced calculators and circuit guides • Full-text topic search • Save favorite circuits for quick access The application contains the following guides and calculators: Amplifiers • Non-inverting operational amplifier • Inverting operational amplifier • Inverting amplifier with T-bridge in OS • Differential amplifier • Differential amplifier with T-bridge in OS • Voltage repeater • Inverting voltage repeater • AC voltage amplifier • High Input Impedance AC Voltage Amplifier • AC voltage repeater ActiveFilters • Non-inverting low-pass filter • Inverting low-pass filter • Non-inverting high-pass filter • Inverting high pass filter • Bandpass filter • Gyrator Integrators and differentiators • Voltage integrator • Sum integrator • Integrator with signal amplification • Difference integrator • Double integrator • Voltage differentiator • Sum Differentiator • Differentiator with T-bridge • Differentiator with T-bridge made of capacitors • Difference differentiator Comparators • Comparator • Limiter • Limiter with zener diode at the input • RS trigger Attenuators • Non-inverting attenuator • Inverting attenuator Converters • Voltage-to-current converter with non-inverting input • Voltage to current converter with inverting input • Voltage to current converter with differential input Adders and substactors • Inverting adder • Addition-subtraction circuit • Non-inverting adder Logarithmic and exponential amplifiers • Diode-based logarithmic amplifier • Transistor-based logarithmic amplifier • Diode exponential amplifier • Exponential transistor amplifier • Popular operational amplifiers description and pinout Sine Wave generators • Op-Amp Oscillators • Oscillator with Diode in the Feedback Path • Twin-T Network Signal Generator Square-wave pulse generators • Op-Amp Square-Wave Generator • Adjustable Square-Wave Generator • Enhanced Square-Wave Generator • Duty-Cycle Adjustment • Triangle and Square-Wave Generator • Generator with Adjustable Slope and Duty Cycle Triangle-wave signal generators • Nonlinear Triangle-Wave Generator • Variable-Symmetry Sawtooth Generator • Linear Triangle-Wave Generator • Adjustable Linear Triangle-Wave Generator • Variable-Symmetry Ramp Generator Download now and power up your electronics work!
Screenshots
Verdict
The clearest difference is rating: Operational Amplifiers Pro at 5.0 against Dialing Code's 3.0. Operational Amplifiers Pro also leads on update cadence (every 2 months vs every 17 months) and iOS requirement (17.0 vs 26.0). Dialing Code's advantage is price ($1.99 vs $4.99). On ratings volume, ads, in-app purchases and monetization model 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
Dialing Code costs $1.99 and Operational Amplifiers Pro $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Operational Amplifiers Pro holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively.
Dialing Code ships an update every 17 months, Operational Amplifiers Pro every 2 months. Both last shipped on October 19, 2026.
| Parameter | Dialing Code | Operational Amplifiers Pro |
|---|---|---|
| Price | $1.99 — better | $4.99 |
| Rating | 3.0 (2 ratings) | 5.0 (1 ratings) — better |
| Positive reviews | 50.0% of reviews | — |
| Number of ratings | 2 — better | 1 |
| Update frequency | Every 17 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Devices | iPhone, iPad | iPhone, iPad, Mac — better |
| Requires iOS | 26.0 | 17.0 — better |
| Further details — not scored | ||
| Size | 5 MB | 14 MB |
| Age rating | 4+ | 4+ |
| Developer | LionsApp di Nallbati Elton | ALG Software Lab |
Customer experience
Dialing Code
Operational Amplifiers Pro
In-app purchases
Dialing Code
No in-app purchases
Operational Amplifiers Pro
No in-app purchases
Questions
Is Dialing Code free?
Is Operational Amplifiers Pro free?
Which has better reviews, Dialing Code or Operational Amplifiers Pro?
Do Dialing Code or Operational Amplifiers Pro have ads?
Which is updated more often, Dialing Code or Operational Amplifiers Pro?
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