Akaba's A500 takes a different approach when it comes to heads-up displays, opting for a direct view display rather than projecting data onto the windshield. This HUD can combine ODB and GPS data to display what is going on inside the car, and it can also perform acceleration and braking tests. With all these features, the price of $90 seems reasonable.

At $90, the Akaba A500's price is double the price of other high-performance HUD units on the market. However, the unit makes up for it by displaying a lot of operational data. It is the only in-vehicle device the company sells in the U.S.

. Rather than laying flat on the dashboard, the Akabane A500 stands upright; at 4.3" x 3.3" x 2.9", it is one of the largest HUDs, but its 3.5" display is the smallest. It weighs 5.1 oz.

Because the Akabane A500 is designed to face the driver rather than project data onto the windshield, the textured black plastic case has a stand that allows the angle of the display to be adjusted. The box also includes an Allen wrench to tighten the stand and prevent wobbling. The screen does not have anything like the Dagood A8's light sensor, which can automatically adjust brightness, but the A500 has an eyebrow extension to reduce stray light reflection from the sun.

Rather than relying solely on OBD data, the A500 has a built-in GPS receiver that not only helps measure speed, but can also perform braking and acceleration tests. However, it cannot display maps or provide directions.

The A500 comes with a 69-inch flat cable to connect to the car's OBD port, which can be easily hidden in a gap in the dashboard. With no on/off switch, the A500's three-button interface may be a tricky way to decide what to display.

With 60 items to choose from, parameters are grouped into nine groups and can display everything from vehicle speed and engine RPM to voltage and engine temperature. In other words, trying to set up the screen the way you want it can be a daunting task.

The HUD can warn the driver of the need to shift gears or to drive too fast. It can also indicate the presence of OBD faults under the hood, but without the codes needed to identify them. The system also lacks phone integration, which could be used to display text messages and directions.

Although it is compatible with a wide variety of vehicles manufactured since 2010, the A500 does not work with every vehicle on the road. For example, Akaba warns that the A500 is not compatible with hybrids, diesel vehicles, and some trucks.

The OBD connector is short enough not to get in the way, but like many other connectors, it can be difficult to grip when trying to remove. In other words, have a pair of pliers handy. Unlike other HUDs on the market, the A500 does not have a rubber mat. Instead, it comes with an adhesive to attach it to the dashboard.

The A500 comes with a one-year warranty and a short 8-page fold-out booklet that explains the basics of the device. There is no troubleshooting section or list of operating parameters, so it took some trial and error to get the meter set up the way I wanted it.

The moment I plugged the A500's OBD connector into the diagnostic port of my 2014 Audi A4 Allroad, the HUD unit was ready to go. There is no dedicated power switch, although the screen automatically turns off when the car is stopped. Rather, it's what I have to make sure the unit isn't draining the car's battery.

The A500 worked well on the street, displayed details of the car's operation, and provided a nice auxiliary set of digital meters, especially for cars without tachometers.

My favorite setup was a dial tachometer that displayed the vehicle speed in the center, several key parameters on the sides, and a compass heading below that. The A500 responded quickly and accurately to my driving and could be read from different angles. Happily, there is no diffuse reflection, which is common with projection HUDs, but in direct sunlight, there is some white-out.

Sadly, the A500 can indicate the presence of an OBD fault, but does not tell you what it is. Therefore, you need to keep your best OBD-II scanner in the glove box.

The A500's last trick is popular with the performance-minded: the A500 can perform acceleration and braking tests to accurately measure how long it takes to get up to speed or back to a stop.

One of the most expensive in-vehicle heads-up displays, the Akaba A500 is big, bold, and can obstruct the driver's view. It is easy to start using, but its ability to display so much on-road data makes it confusing and difficult to adjust.

Once you find a layout that suits your needs, the A500 can be a great tool - especially with the built-in OBD and GPS features. The fact that the sunlight didn't affect the forecast too much was also a bonus.