A Hong-Kong-based company is on a mission to push the product called SonarPen, which is a cheap, pressure-sensitive stylus that works on almost all generations of iPad, connecting to the devices through the headphone jack.
The SonarPen is an interesting smartpen that cleverly fills the gap in the market between a cheap rubber stylus and a more expensive Apple Pencil. The battery-free device connects to an iPhone or iPad, via the headphone jack or lighting adapter if you have a newer model. The pen's pressure-sensitive capabilities are produced by turning the pen strokes into audio signals, these are interpreted as digital signals by the tablet or smartphone and instantly transformed into writing on the screen.
The SonarPen is currently only available for iOS devices. Android tablet and smartphone users can still utilise the device but, currently, it will only work as a "dum stylus" with no pressure-sensor palm-rejection capabilities. It is claimed that Android integration is on its way and very well may be around by the time the device ships in June.
There are only two iOS apps that are officially supported by the SonarPen; Zen Brush 2 and ZoomNotes, but the makers of SonarPen suggest several more app developers are currently working on, or reviewing, to integrate the smart features of the device. The cost of the SonarPen is its strongest feature with a current early bird campaign price of around $25 (USD) with a post-campaign regular retail price of $30.
Take a look at the campaign video below to learn more about the SonarPen.