The brightness of your portable projector will largely be determined by the intended use. In most cases the more brightness the better but of course this will affect the portability. The more powerful the projector is the larger the chassis will be to hold the bigger and more powerful electronic components. Typically the smallest pocket sized projectors will be a mere 200 lumens requiring a dark environment and small image size. The slightly larger more powerful portable projectors of 1000 lumens will still require a dimmed room but are still quite small. While a lights on power level 3000 to 4000 lumens will be a larger more typical sized chassis.
Smart functions can make a projector even more portable. With inbuilt Windows or Android operating systems a projector can save you transporting extra devices to a business presentation. Some of the newer windows and Android smart projectors allow you to use it as a stand alone smart device. Essentially a projector with an inbuilt laptop allowing you to control it with a keyboard and mouse and even allowing you to attach a webcam for video conferencing.
For personal entertainment portable projectors come with inbuilt Android TV which allows you to run regular streaming apps without extra devices to transport. Able to connect to your home Wifi or a hot spot they can download apps subscription or free and stream tv shows or movies with ease.
Portable projectors utilizing mains power will be lighter due to the lack of battery and in many cases more powerful. Without trying to stretch a battery pack run time the power output or brightness can be much higher. The downside is that you would need a source of power whether it is a generator in a remote areas or a wall socket in a regular setting.
Portable projectors with an inbuilt battery are a truly portable device with the ability to move around freely without cables and even do a great job for entertainment in the great outdoors. The brightness of the battery powered projectors will typically be lower to allow them to work off a reasonably light weight battery. Run time of a battery powered projector will vary but usually they are around 2 hours. Some projectors while not equipped with a battery inbuilt can be attached to external battery packs with USB-C power delivery.
We have some of our favourite home projector recommendations below. We know it can be difficult to pick the best one for you so if you need assistance please send us an email with your requirements, we are happy to help.