Comparison

SigTrax vs Smith Charts

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

Head to head
About

SigTrax

This app helps users locate signal origins by plotting bearings and identifying intersection points. It simplifies the tracking process with mobile device capabilities, offering features like automatic Crosspoint calculation and driving directions to identified locations.

Highlights
  • Plot bearings and determine Crosspoints
  • High precision GPS locating
  • Handheld mapping
  • Automatic Crosspoint management
  • Driving maps with voice routing
  • Archive and retrieve bearing collections
Read full description

Signal Tracking Toolkit SigTrax is the signal tracker’s toolkit combining the power and visual capabilities of IOS mobile devices with high precision GPS locating and hand held mapping to plot bearings and determine Crosspoints™, locations where bearing lines cross, potentially the location of a signal’s origin. THE SIGTRAX DIFFERENCE Signal tracking has always been a vital resource, assisting in emergency situations,locating interference or noise sources and serving as a valuable asset for spectrum monitoring. SigTrax expands this resource by supplying tools that allow signal trackers to find the origin of signals faster with more accurate results. SIMPLIFY THE TRACKING PROCESS The advent of mobile smart devices allows us to have tools that before were either non-existent or like the signal trackers collection of papers, maps and marking instruments, unwieldy to carry and use. With SigTrax, manually handling maps, plotting intersection points and determining a route to reach an intersection point is eliminated, simplifying searches resulting in faster and more accurate results. BEARINGS AND CROSSPOINTS™ Bearings are lines from a starting coordinate toward a compass heading as an indication of the approximate direction of a signal. Bearings can be entered into SigTrax in multiple ways, selectively viewed, edited or deleted. Bearing collections can be archived then retrieved at a later time, vital when tracking signals over long time periods. Crosspoints, locations where bearing lines intersect, are automatically managed when bearings are added, deleted or edited. Driving maps complete with text and voice routing instructions direct the user to a Crosspoint location. EASY TO USE The SigTrax user interface was designed to be simple and easy to use in less than ideal conditions. SigTrax can be customized to individual preferences and needs using the Settings function. A complete User Guide is included for quick reference. SigTrax+ OPTIONAL FEATURES SigTrax+ optional purchasable features expand the signal tracking toolkit. SigShare™ allows bearings and archives to be displayed in a large format such as Google Earth, ideal for presentations. DataTrax™ is a smart interface that automatically inserts and plots bearing generated from external systems such as Doppler. The SigTrax website details DataTrax features and requirement. TraxTeam™ allows cooperative hunting, a foundation of signal tracking, that greatly extends the possibility of a successful and timely hunt, vital in emergency situations. Multiple trackers form a TraxTeam™ instantaneously sharing bearing information with the hunt group. REQUIREMENTS Requires IOS device with GPS and internet access to obtain map images. FURTHER INFORMATION Check the SigTrax web site to discover the SigTrax difference. Be sure to explore the video series and User Guide to learn more about the benefits of signal tracking with SigTrax. SUBSCRIPTIONS SigTrax offers auto-renewing subscription as in-app purchases to access TraxTeam. TraxTeam 3 Month is a three-month access to TraxTeam. TraxTeam One Year is a one-year access to TraxTeam. Please read about the auto-renewing TraxTeam subscriptions before purchasing. Payment will be charged to your iTunes account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period, and identify the cost of the renewal. Subscriptions may be managed by the user and auto-renewal may be turned off by going to then the user's Account Settings after purchase. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to a product. Please review the TraxTeam terms-of-use policy: www.sigtrax.com/tos.html and our privacy policy at www.sigtrax.com#privacy.

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.

Screenshots

SigTrax4 screens
Smith Charts4 screens

Verdict

The call

The clearest difference is in-app purchases: Smith Charts at none against SigTrax's 2. Smith Charts also leads on update cadence (every 3 weeks vs every 3 months) and chart position (#199 vs unranked). SigTrax's advantage is price ($2.99 vs $3.99). On rating, review sentiment, ratings volume and ads 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

SigTrax costs $2.99 and Smith Charts $3.99 up front. SigTrax sells 2 one-off in-app purchases. Smith Charts asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 3.6 for SigTrax against 3.7 for Smith Charts. Both are backed by a comparable volume of ratings — 8 and 3 respectively. Written reviews are what separate them: 60% of SigTrax's written reviews are positive against 67% of Smith Charts's.

UpkeepUpdate frequency

SigTrax ships an update every 3 months, Smith Charts every 3 weeks. The most recent releases landed on October 6, 2026 and October 8, 2026 respectively.

Scorecard4 real differences · 7 level
SigTrax versus Smith Charts: the parameters behind the verdict, then further details
ParameterSigTraxSmith Charts
Price$2.99 — better$3.99
Rating3.6 (8 ratings)3.7 (3 ratings) — better
Positive reviews60.0% of reviews66.7% of reviews — better
Number of ratings8 — better3
Update frequencyEvery 3 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationPaidPaid
Best chart rank—#199 — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size5 MB24 MB
Age rating4+4+
DeveloperAmcept, LLCEdoardo Orzes

Customer experience

SigTrax

All ratings8 ratings
Positive62.5%
Neutral12.5%
Negative25.0%
Written reviews5 reviews
Positive60.0%
Neutral0.0%
Negative40.0%

Smith Charts

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

In-app purchases

2 purchases

SigTrax

One-time2
  • SigShare$1.99
  • DataTrax$5.99
None

Smith Charts

No in-app purchases

Questions

Is SigTrax free?
SigTrax costs $2.99, and also offers in-app purchases.
Is Smith Charts free?
Smith Charts costs $3.99, with no in-app purchases.
Which has better reviews, SigTrax or Smith Charts?
Smith Charts is rated higher. SigTrax averages 3.6 out of 5 from 8 ratings, while Smith Charts averages 3.7 from 3 ratings.
Do SigTrax or Smith Charts have ads?
Neither SigTrax nor Smith Charts shows ads.
Which is updated more often, SigTrax or Smith Charts?
SigTrax ships an update every 3 months, and Smith Charts every 3 weeks. Most recently, SigTrax was updated on October 6, 2026 and Smith Charts on October 8, 2026.

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