Smith Chart for iPhone and iPad is a graphical design tool for microwave and RF engineers, as well as students and educators. This powerful, yet easy to use application replaces the traditional paper Smith chart used for years to facilitate impedance matching between electronic components.

At the start of the application, a Smith chart is displayed on the screen. A fixed or frequency dependent source and load are defined, and automatically appear on the chart. Matching components may then be added from an on-screen menu of lumped and distributed elements. When one of the elements is selected, a trace appears on the Smith chart, representing a wide range of impedance values of that particular component. The user then moves a cursor, which tracks his finger, to the desired location on the trace. Upon lifting his finger, the component value corresponding to the cursor location is recorded, and the trace ends at that location on the chart. The designer then adds another component, whose trace starts at the end of the previous trace, and then another, until the matching is complete. At any time during the design process, a swept frequency analysis may be performed with the touch of an on-screen button. The design frequency, start and stop frequencies and the number of points for swept analysis may all be set by the user. VSWR, real-time cursor tracking, various types of loads and sources (fixed or frequency variable) are all user definable as well.

All components are editable, either in matching or swept frequency mode, so tuning can be accomplished over frequency. Zooming and panning are supported, and a compressed Smith chart may be displayed. A full schematic of the matching circuit is automatically generated and may be displayed at any time. Convenient camera buttons are available for photo documentation of the Smith chart design and the generated schematic.

This app is a real time saver for design engineers who like the intuitive feel of designing with a Smith chart, but who would like to avoid the tedious calculations.

Requires IOS 7.0 or higher.

What’s New

Version 2.3

Bug Fix
Added optional 'Q' tracking

Ratings and Reviews

4.0 out of 5
1 Rating

1 Rating

Pidloop ,

Great start

Overall design and core features are good. But pretty awkward to keep going back and forth to change values .. would be great if values could be changed by dragging on the chart.

N6NZ ,


Needs two things to be ready for prime time: 1. Need to be able to specify a frequency dependent load as a table of Z’s. Without that, frequency sweep is kind of pointless and it isn’t very useful for antenna matching. 2. Should be able to adjust component values by dragging a connection on the Smith chart. As it is, you have to keep going back and forth to the numeric entry tab for the components.

EMC Engineer ,

Best Smith Chart Tool

Amazing app and so very useful as a teaching tool, a learning tool, and true day to day engineering tool. Because this app I purchased a lightning to HDMI cable adapter so that I can project Smith charts to large groups.

By far the best Smith Chart app and I recommend this to all students, electrical engineers, RF engineers, for board layout, and physicists.

This tool has it all, custom components, quality circles, VSWR circles, ability to save files, share designs with others, cursor readout, and more. The schematic view allows for easy entering the finished design into SPICE programs.



Seward Salvage
5.2 MB

Requires iOS 7.0 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
Rated 4+
© Seward Salvage 2012


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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