Moment's new app update gives you the ability to take long exposure photos with your phone, and export it as video or live photo. And it's very well implemented.
As a practice run, I just took some images of my train trip this morning and another while I was walking across the bridge in Paris. It's not just easy to use, but it does change the way you approach your shot, and it makes me want to try new things, even if it's not related to my style of photography.
You've Got Two Options
You can set it up for motion blur or for light trails, and with each of these, you can change exposure time (4, 8, 15, 30 and Bulb). If you use your phone to take pictures, and let's be honest, we all do, this could give you some more options when you're out without your camera. It might even be that this technology transfers to our DSLR or mirrorless cameras one day too.
Conclusion
If you carry your phone with you, and we all know you do, the Moment app has another feature that is not found in other apps. And what's even more than that, is that it's implemented in a very good way. I'm stoked about them developing new technologies, and that with great lenses to create a compact kit you can take anywhere.
The only advice I have is that you have a sturdy tripod, and that you use your Apple smartwatch to trigger the photo, because any shake will be seen in the end result, and the flat surface of the phone is not the ideal for windy places.
Check out the site for more information.
The closest thing I've seen to this iOS/Android app on a mirrorless camera is the Sony Play Memories App called Smooth Reflection https://www.playmemoriescameraapps.com/portal/usbdetail.php?eid=IS9104-N.... Here's the promo video for it: https://www.youtube.com/watch?v=sPXlUOkJ3Fw
I have this app on my Sony A7R2 and it's pretty awesome. Though this app works great, there are still times in which you would want to actually put an ND filter onto the front of your lens.
The Sony app gives you the ability to shoot "long exposures" without the use of an ND filter on your Sony mirrorless camera. It works by taking multiple RAW files over the course of several seconds to several minutes (depending on the settings you choose), and combines and processes the smooth motion all in camera. The final image is a RAW file with motion blur. Unfortunately, Sony stopped development of Sony Play Memory apps and took this ability away for A7R3 shooters, I still have it on my A7R2 and it's a great tool to have. It was a pain to download and continually update, but a really great way to expand the capabilities of your mirrorless camera. I personally think downloadable apps for mirrorless cameras was a great idea and potentially the future of mirrorless cameras. Maybe this concept was before it's time, who knows.
The advantage of the Moment app is the unlimited shutter length which I believe you can otherwise do only with the Camera+ app. But for handheld use, the Spectre app does a pretty good job with its AI Stabilization to allow hand-holding for 3, 6, or 9 seconds. I had to overshoot to find a crisp specimen, but I got a pretty nice 9 second shot of waterfalls a few months ago completely handheld.
If you don't mind a very short shoot length, you can also convert any Live photo to a long exposure fixed photo simply by viewing the Live photo in the Apple native app, and swiping up and to the right and selecting Long Exposure,
I would think the need for a tripod defeats the portability and simplicity of using the phone.
True, but you can use almost any flat, fixed object to brace your phone.
This is a great app but another example of how automated processing/photography is making creative photography more accessible to the masses....for better or worse. The thing I've always liked about photography and most hobbies was the process of learning and practice required to continually improve your skills.
Huawei has had this in their photo app for a while now.