Papiosaur describes Momento as an "image manager and viewer for MorphOS". The version I'm reviewing is version 1.4, released on the 15th of May, 2026.

Here are my experiences:

Anything a megabyte or larger produces a small ~1 second delay in previewing, and the images loaded from a folder are not cached, so the ~1 second delay always occurs, bear in mind. This delay increases with the file size of an image, not necessarily the resolution of an image. For example, I loaded a folder of morpho butterfly pictures in Momento 1.4 and an image with a resolution of 1920x1080 but a file size of 500 kilobytes loaded instantly, but a 3.41 megabyte image with a resolution of 1560x1040 took about 2 seconds to load and preview. This is natural. I do like that Momento displays the file size and resolution of images, which is very helpful for me.

Depending on the size of the image, CPU usage on a Mac Mini 1.5 GHz hovers anywhere from 20-40% usage. Idle CPU usage rests at an impressive 4%! I think this is due to Momento being written in C, which is an exceptional programming language. What’s just as impressive is the initial import of a directory. I imported a folder of 144 images in about 1.5 seconds with a spike in CPU usage to ~20%. That’s amazing. Dragging/moving the Momento window while an image was loaded/previewed lagged Momento and spiked CPU usage to about ~80%. This occurred regardless of the file size of a particular image loaded/previewed, or even with no image loaded at all.

I might have encountered a bug when testing Momento. I removed a directory I imported, so Momento defaulted its selection to the previous directory and proceeded to recycle/reload about 4 times before it stopped. Upon redoing the same thing, Momento didn’t do this a second time. This occurrence may be sporadic.

Another thing to note is that the user must actually be within the folder they wish to import before pressing the “OK” button. I selected the Work volume, then selected the directory I wished to import, but Momento imported the entire Work volume instead. When I double-clicked the directory I wished to import, instead (thus bringing me inside the directory), Momento imported the directory I wished to import. I simply had to retrain my brain after witnessing this happen the first time.

Conclusion:

Momento is pretty quick, light on system resources, and most importantly ... does it what it sets out to do! There's a number of MorphOS software from bygone years that are either malfunctioning and abandoned or are very ill-optimized. I may or may not review some of those in the future.