If you use a phone, tablet or computer, the internal microphone of the device can be very good, depending on the class of the device itself. You need a clean and intelligible sound, not studio quality. Standard sound recording applications built into mobile devices are usually designed for voice. They limit the frequency response, suggesting that only voice will be recorded. This allows you to get fairly compact files on the output, saving on the sound quality. Well, there quality, as a rule, is not particularly necessary. We used iPhone to record audion and video for promo for https://homeworkneeded.com/ and it went pretty solid. It makes sense to buy yourself an external device for a mobile device, something like an external sound card. Usually, they quickly start up, record up to 4 channels at the same time in high quality, provide the ability to quickly transfer recorded files and have on board a DSP processor for processing audio, which takes these calculations on itself - actual for weak mobile devices.
When using a portable recording device, you need to remember to regularly transfer files from it to the main large hard drive from it, so as not to interfere with the situation when you need to fix the idea, but there is no free space. And there is no place to throw off existing files. In addition, on our phones and tablets are often a lot of games, music, movies, etc.