Smartphone Stylus
Credit: dreamjay @

With recent developments in touchscreen technology and smartphone performance, smartphones can now respond to very rapid and precise touch gestures. But unfortunately, your finger is not very precise. That's why using a smartphone stylus can greatly enhance the value of your cellphone, making it much easier to navigate, alternate between multiple screens, choose apps, type on the keypad, and dial phone numbers. Let's take at a look at the three main types of smartphone screens and how they operate to determine what type of stylus is best for each.

Resistive Touchscreens

Resistive touchscreens require pressure from a finger or stylus to operate. Despite the fact that this kind of technology may be extremely accurate, it is commonly an attribute of lesser-quality smartphones because it lacks multi-touch support. Consumers can touch the screen with multiple fingers or stylii, but the display will only respond to the very first pressure source.

This technology is relatively basic. It makes use of a coordinate grid with X-Y axes, with tiny cables inlayed between two sheets of bendable and resistive plastic material. Once the sheets are pushed together they generate added resistance to the current moving through the grid cables. The specific wires sensing the change in electrical current produce an X-Y coordinate for the touch input.

The Best Resistive Stylus

Since resistive touchscreens respond entirely to pressure, virtually everything will do the job, from a simple cheap stylus to a fingertip. What ultimately matters here is what you're planning to use your stylus for. For instance, a touch or tap function is best suited to a rubber-tipped smartphone stylus, while electronic signature functions are more effective with a smooth-tipped stylus that slides effortlessly over the screen.

Capacitive Touchscreens

Capacitive touchscreens are extremely clear, providing as much as 90 percent transparency. They are created to react to the electrical patterns of a human finger. A tiny electrostatic field is produced all over the screen's display, and as soon as anything starts absorbing that power, the field is interrupted. This interruption is detected by receptors in different areas around the display. These receptors then translate the X-Y points of the contact into a touch coordinate.

These kinds of touchscreens are quite sensitive, which explains their use in such a large number of smartphones and other electronics, but they do require a particular amount of surface space to be touched in order to react. Specifically, a particular amount of electrical energy must be absorbed in order for a touch to be detected, and that may be a bit of a challenge for users in situations where direct contact with a finger is difficult (e.g. if you're wearing gloves). It also results in significant difficulties for stylus manufacturers who must design special tips capable of absorbing the electrostatic current similar to a human finger.

The Best Capacitive Stylus

In contrast to resistive touchscreens that can use practically anything, a capacitive touchscreen needs a customized stylus that can imitate the electrical qualities of a human finger. This demands that it be created with particular dimensions or out of particular materials. To figure out if your smartphone uses a capacitive screen, the quickest way to check is to try something like a smooth plastic pen cap. If it doesn't respond to the pen but does respond to your finger, it is very likely a capacitive touchscreen and needs a special smartphone stylus. 

SAW Touchscreens

In addition to smartphones, many Point Of Sale (POS) devices, like cash registers, order screens, and kiosks, use Surface Acoustic Wave (SAW) touchscreens. These mechanisms all operate by producing quiet sound waves all over the display screen. When the movement of the sound waves is disrupted by the touch of an object with sufficient mass, an X-Y value is translated into a touch coordinate.

The Best SAW Stylus

In order for a stylus to function on a SAW screen, it will need the ability to absorb nearly as much sound as a finger. This usually calls for a soft or rubber-tipped stylus that has, at a minimum, the mass of a pencil eraser. 

Resistive, capacitive, and SAW are the most common types of touchscreens on the market. If you're looking for a stylus for your smartphone, you will most likely be looking for a capacitive stylus, as most modern cellphones have a capacitive screen. Still, be sure to double check what kind of screen your specific phone has, either using the quick tests suggested above or by researching on the internet, so you don't waste your hard earned money!