Comparison

Smith Charts vs Grindcalculator

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

Grindcalculator

This tool simplifies knife sharpening by calculating the correct angle, eliminating the need for manual marking. Save custom sharpening angles and grinding wheel dimensions for consistent results across various brands and types of sharpening tools.

Highlights
  • Precise angle calculation
  • Eliminates manual marking
  • Save custom angles
  • Save grinding wheel dimensions
  • Supports all grinder brands
  • Offline functionality
Read full description

The sharpening calculator is the perfect tool for sharpening knives. Especially when sharpening knives, it is important that the correct angle is resharpened. Most manufacturers, such as Tormek, Einhell, Scheppach, Record Power and many others supply an angle gauge specially designed for the machine. It takes a lot of practice to set the machine correctly with the gauge in order to be able to sharpen the correct sharpening angle on the knife or any other sharpening piece. Professionals often mark their phase to adjust the toolbar to the correct height. We developed the sharpening calculator app to make it easier to sharpen or sharpen knives and, above all, to get a consistently good sharpening result. The annoying phase marking is no longer necessary. Just like the complicated application of the angle gauge to the clamped sanding pad and the adjustment of the toolbar. There is almost no limit to the detection of grinders, grinding wheels and grinding pieces. Grinding pieces are, for example, kitchen knives, wood chisels or planer knives. Everything that can be ground with a wet grinding machine. After the app has been installed, the basic dimensions for the top toolbar, the front bar and, if available, the front base must be entered as described in our tutorial. The values can be adjusted at any time if you have measured yourself. The grinding wheels can either be saved or adjusted again for each grinding process. Here it is important that CBN wheels, for example, always have the same diameter, but wet grinding stones lose diameter through use. This value must be adjusted before grinding. The grinding calculator is suitable for probably every grinding machine from all manufacturers. Even individual structures can be used. Many app users have bought various grinding wheels from, for example, grinding junkies. The grinding calculator also works perfectly for this. With some polishing wheels, an angle correction can be stored so that polishing works even better. If you have recurring sharpening pieces such as kitchen knives, it is possible to save them with the respective sharpening angle. This eliminates the need to measure the angle again when resharpening and everything goes much faster. The grinding calculator is now also available for the iPad. All functions can be used. If you allow access to the iCloud, then all entries are synchronized between the devices. This means that all devices, grinding wheels and grinding pieces are synchronized on all devices used such as iPhone and iPad. This process is also the only thing for which the grinding computer needs an internet connection. Otherwise, the app works anytime, anywhere, even without an active internet connection. With family sharing, each user has their own database. It is currently not possible to share your own devices between users. Further features are described on our website https://www.grindcalculator.de. The procedure is described in detail in the operating instructions, which can be found under the URL https://www.grindcalculator.de/tutorials/operation-manual.

Screenshots

Smith Charts4 screens
Grindcalculator4 screens

Verdict

The call

The clearest difference is rating: Smith Charts at 3.7 against Grindcalculator's 1.0. Smith Charts also leads on price ($3.99 vs $6.99) and ratings volume (3 vs 1). Grindcalculator's advantage is update cadence (every 4 days vs every 3 weeks) and review sentiment (85% vs 67%). On ads, in-app purchases, monetization model 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

Smith Charts costs $3.99 and Grindcalculator $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Smith Charts holds the better App Store score, 3.7 against 1.0. Both are backed by a comparable volume of ratings — 3 and 1 respectively. Written reviews complicate that: 67% of Smith Charts's written reviews are positive against 85% of Grindcalculator's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Smith Charts ships an update every 3 weeks, Grindcalculator every 4 days. Both last shipped on October 24, 2026.

Scorecard6 real differences · 4 level
Smith Charts versus Grindcalculator: the parameters behind the verdict, then further details
ParameterSmith ChartsGrindcalculator
Price$3.99 — better$6.99
Rating3.7 (3 ratings) — better1.0 (1 ratings)
Positive reviews66.7% of reviews84.6% of reviews — better
Number of ratings3 — better1
Update frequencyEvery 3 weeksEvery 4 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better26.0
Further details — not scored
Size24 MB9 MB
Age rating4+4+
DeveloperEdoardo OrzesRoWo UG

Customer experience

Smith Charts

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

Grindcalculator

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews13 reviews
Positive84.6%
Neutral0.0%
Negative15.4%

In-app purchases

None

Smith Charts

No in-app purchases

None

Grindcalculator

No in-app purchases

Questions

Is Smith Charts free?
Smith Charts costs $3.99, with no in-app purchases.
Is Grindcalculator free?
Grindcalculator costs $6.99, with no in-app purchases.
Which has better reviews, Smith Charts or Grindcalculator?
Smith Charts is rated higher. Smith Charts averages 3.7 out of 5 from 3 ratings, while Grindcalculator averages 1.0 from 1 ratings.
Do Smith Charts or Grindcalculator have ads?
Neither Smith Charts nor Grindcalculator shows ads.
Which is updated more often, Smith Charts or Grindcalculator?
Smith Charts ships an update every 3 weeks, and Grindcalculator every 4 days. Most recently, Smith Charts was updated on October 24, 2026 and Grindcalculator on October 24, 2026.

Other comparisons