Comparison

Smith Charts vs X Speed Reader

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

Head to head
About

Smith Charts

Design matching networks, analyze device parameters, and compute stability circles with this interactive tool. Supports S parameters, various components, and offers advanced engineering features for RF design. Available in dark mode and exportable to PDF.

Highlights
  • Interactive Smith chart with drag and zoom
  • Design matching networks with various components
  • Compute stability, equi gain, and noise circles
  • Import S parameters from Touchstone files
  • Export designs to PDF, image, or file
  • Dark mode support
  • Ruler for wavelength measurement
Features
Read full description

A great experience of the Smith chart. Also in dark mode. Design matching networks, insert S parameters and convert them, or import from touchstone file. Compute stability circles, equi gain and noise circles.  Easy interaction with the Smith chart. This chart can easily replace a physical one, making its use much faster. Smith chart interactivity: - Works on iPhone, iPad and Mac (on Apple Silicon). - Drag and zoom in the chart. - Create multiple Smith Charts and name them. - Switch easily between input and output planes. - Use a ruler and drag it to obtain the wavelength toward generator of a point on the chart, instantly. - Tap the chart to show the coordinates in algebraic notation, you will see also magnitude and phase of that location, and the corresponding impedance. - Insert circles by hand; modify the radius dragging a circle to keep the center in place, or press to translate them and modify the radius keeping the opposite side in place. Then use the padlock button to disable interaction of gestures with circles. - You can also insert a custom circle and a segment in the input and in the output plane, defining its center and radius in a textfield. - Export to file, image or PDF Advanced tools for engineering: Matching networks: - Choose electronic components to design a matching network for your device. - Available components are: L, C, R, Z and lines (transmission line, parallel or series stub, open or shorted). - For each component it is possible to specify the parasites. - For transmission lines, it is possible to choose between Z0, K or L, C representations, and converting between the two (also for parasites). - Tapping on a component it is added to the network and the impedance seen from your device toward the matching network is shown on the smith chart. - You can create a matching network both for input and output planes of the device. - Each network has its own termination (source or load), which can be a one port device or a two ports device where you can choose a termination for the second port. - Each termination can be defined by network parameters (S, Z, Y or h) and the parameters can be imported from a touchstone file. - Components supported: Resistor, Capacitor, Inductor, General impedance (R+jX), Transmission line, Parallel stub, series Stub (both shorted or open). - Each component can be cascaded in series or in parallel, no limits of components. - You can choose a frequency for the impedance calculation and a frequency span for the plot on the Smith Chart. - For S parameters, you can specify a dedicated characteristic impedance, the tool will renormalize the Γ of that termination to be correctly shown on the Smith chart, when the smith chart is defined on a different characteristic impedance. Device analysis: - You can insert the following parameters of a device: network parameters (S, Z, Y or h), specifications (Ga, Gp, Gt, NF), noise data (gamma s optimum noise, minimum NF, rn) and the input/output reflection coefficients. - You can convert network parameters (S, Z, Y, h), and the port type (Γ, Z, Y). - While you are inserting data, you will see the computed results appearing on the chart and on the relative fields. - Results representable on the smith chart: input/output stability circles, power gain and noise circles (equiGa, Gp, Gt, NF circles), reflection coefficients towards load and source and optimum power coefficients. - Other results: obtained power gains and noise (Ga, Gp, Gt, NF) and stability (D, K, kind of stability). - You can display on the Smith chart the input impedance of your component versus frequency (as a function of load impedance) when importing a touchstone file. - For S parameters, you can specify a different characteristic impedance and the tool will automatically convert it to the one defined for the Smith chart, it will let you know the new renormalized parameters.

About

X Speed Reader

Features
Read full description

X Speed Reader helps you get through X articles faster using RSVP (Rapid Serial Visual Presentation): words appear one-by-one at your chosen speed, so you can focus on comprehension with fewer distractions. Features • Read X articles with the best RSVP reader • ORP highlight • Reading history • Continue reading where you left off • 200-1000 WPM reading speed Reading full articles require paid premium subscription. Terms of Use: https://sad-team.notion.site/Terms-of-Use-2efad671ba82815792b1db4ee74c2821

Screenshots

Smith Charts4 screens
X Speed Reader4 screens

Verdict

The call

The clearest difference is price: X Speed Reader at Free against Smith Charts's $3.99. X Speed Reader also leads on update cadence (every 5 days vs every 3 weeks). Smith Charts's advantage is in-app purchases (none vs 3) and chart position (#196 vs unranked). On 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

X Speed Reader is free to download; Smith Charts costs $3.99 up front. X Speed Reader sells 3 in-app purchases, starting at $2.99 per month. Smith Charts asks for nothing beyond the download.

UpkeepUpdate frequency

Smith Charts ships an update every 3 weeks, X Speed Reader every 5 days. The most recent releases landed on October 8, 2026 and October 1, 2026 respectively.

Scorecard4 real differences · 7 level
Smith Charts versus X Speed Reader: the parameters behind the verdict, then further details
ParameterSmith ChartsX Speed Reader
Price$3.99Free — better
Rating3.7 (3 ratings) — better—
Positive reviews66.7% of reviews—
Number of ratings3 — better—
Update frequencyEvery 3 weeksEvery 5 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
Best chart rank#196 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.0 — better15.1
Further details — not scored
Size24 MB48 MB
Age rating4+4+
DeveloperEdoardo OrzesOleksandr Kryzhanovskyi

In-app purchases

None

Smith Charts

No in-app purchases

3 purchases

X Speed Reader

Subscriptions2
  • Monthly Premium3 Days trial$2.991 Month
  • Yearly Premium7 Days trial$7.991 Year
One-time1
  • Lifetime$14.99

Questions

Is Smith Charts free?
Smith Charts costs $3.99, with no in-app purchases.
Is X Speed Reader free?
X Speed Reader is free to download, with in-app purchases available.
Do Smith Charts or X Speed Reader have ads?
Neither Smith Charts nor X Speed Reader shows ads.
Which is updated more often, Smith Charts or X Speed Reader?
Smith Charts ships an update every 3 weeks, and X Speed Reader every 5 days. Most recently, Smith Charts was updated on October 8, 2026 and X Speed Reader on October 1, 2026.

Other comparisons