Comparison

i vs RF calculator & Smith Chart

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

Head to head
About

i

Features
Read full description

Get a vibration analysis of your vibration machine in a few seconds. The i-STEP Vibrosense App is only compatible with the i-STEP Vibrosense sensor.

About

RF calculator & Smith Chart

Features
Read full description

RF Calculator & Smith Chart is an all-in-one RF engineering toolkit for impedance matching, RF network analysis, antenna calculations, filters, attenuators and wireless system design. Built for RF engineers, electronics engineers, students, technicians and radio enthusiasts, it brings essential RF calculations and design tools together in one convenient app. Analyze impedance, work with Smith Charts, calculate VSWR and S11, design matching networks, estimate path loss, build RF attenuators and evaluate wireless links without jumping between multiple tools. RF & IMPEDANCE TOOLS • Smith Chart for impedance visualization and matching • S11 and reflection analysis • Reflection coefficient calculator • VSWR calculator • Impedance and transmission-line calculations • Cascaded RF network calculations IMPEDANCE MATCHING Design and analyze common RF matching networks: • L matching networks • Pi (π) matching networks • T matching networks • Stub tuner calculations Useful for antenna matching, RF amplifiers, transmission lines and other impedance-matching applications. RF FILTER DESIGN Calculate and design common passive and RF filters: • RC filters • RL filters • RLC networks • Butterworth LC low-pass filters • Chebyshev LC low-pass filters • Filter designs up to 8th order • Microstrip band-pass filters • Microstrip band-reject / notch filters RLC CIRCUITS Analyze frequency-dependent RLC networks: • Series RLC circuits • Parallel RLC circuits • Resonant frequency calculations • Frequency behavior and reactance RF ATTENUATOR DESIGN Quickly calculate standard RF attenuator networks: • Pi (π) attenuator • T attenuator • Bridged-T attenuator Ideal for RF signal-level control, impedance-matched pads and test setups. ANTENNA & PROPAGATION TOOLS Plan and evaluate RF and wireless systems with: • Antenna design utilities • Free-space path loss calculations • Friis transmission calculations • RF link budget calculator • Power density calculator • Radar maximum-range calculator COMPONENT DESIGN & REFERENCE Useful electronics tools are also included for RF design and prototyping: • Air-core inductor design • Spiral inductor design • Multi-layer air-core inductor calculations • SMD resistor code • Resistor color code • Resistors in series and parallel • SMD capacitor code • Capacitors in series and parallel BUILT FOR PRACTICAL RF WORK RF Calculator & Smith Chart is designed for quick engineering workflows. Select a tool, enter your parameters and get the values you need without working through repetitive equations manually. Use it for: • RF circuit design • Impedance matching • Antenna projects • Wireless link planning • Filter design • RF testing and troubleshooting • Electronics laboratories • Engineering study and coursework • Amateur radio and RF experimentation Whether you're checking VSWR, designing an impedance-matching network, calculating a link budget or experimenting with RF filters, RF Calculator & Smith Chart keeps essential RF engineering tools within easy reach.

Screenshots

i4 screens
RF calculator & Smith Chart4 screens

Verdict

The call

The clearest difference is in-app purchases: i at none against RF calculator & Smith Chart's 1. i also leads on update cadence (every 2 months vs every 4 months). RF calculator & Smith Chart's advantage is iOS requirement (15.0 vs 17.6). On price, ads 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. RF calculator & Smith Chart sells 1 one-off in-app purchase. i asks for nothing beyond the download.

UpkeepUpdate frequency

i ships an update every 2 months, RF calculator & Smith Chart every 4 months. The most recent releases landed on October 30, 2026 and November 5, 2026 respectively.

Scorecard3 real differences · 5 level
i versus RF calculator & Smith Chart: the parameters behind the verdict, then further details
ParameteriRF calculator & Smith Chart
PriceFreeFree
Rating—4.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 2 months — betterEvery 4 months
AdsNoNo
In-app purchasesNo — betterYes
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.615.0 — better
Further details — not scored
Size34 MB31 MB
Age rating4+4+
DeveloperIFE Aufbereitungstechnik GmbHAnas Abubakar

In-app purchases

None

i

No in-app purchases

1 purchases

RF calculator & Smith Chart

One-time1
  • upgrade to pro$3.99

Questions

Is i free?
i is free to download, with no in-app purchases.
Is RF calculator & Smith Chart free?
RF calculator & Smith Chart is free to download, with in-app purchases available.
Do i or RF calculator & Smith Chart have ads?
Neither i nor RF calculator & Smith Chart shows ads.
Which is updated more often, i or RF calculator & Smith Chart?
i ships an update every 2 months, and RF calculator & Smith Chart every 4 months. Most recently, i was updated on October 30, 2026 and RF calculator & Smith Chart on November 5, 2026.

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