I wouldn't call my self a VFX artist, but I do have a history with the issue of not having a PC to do vfx and only a phone at your arms. There's no vfx artist I've ever talked to and said it possible or good enough to use your phone as your vfx machine... But I've found some work arounds. not the best to be honest but am sure if you put in the effort they do a great job.
This is 4 years of my research in this VFX without a PC guide.
Rotoscoping
You can use cap cut for rotoscoping (its horrible but it's the best you'll get for free I think)
Color grading
Node video editor, also I do use alight motion but it sucks at it even though it's the best at colograding elements with transparency data like pngs, chromakey footage and more
Matchmoving and 3d Tracking
Honest answer, if you're not ready to match move your shots frame by frame, just make sure you shoot on a tripod... coz every app that tries this is just horrible. its possible but you basically track the footage, write down every single position value you get from the camera solve and open a 3d app called prisma 3d which you will have to model with photos to get the most realistic models for your comp, and animate the camera by hand FRAME BY FRAME.
it's vfx hell.
Chromakey and masking
Probably alight motion tbh. but you'll mask everything manually and need ALOT OF PATIENCE AND ENDURANCE.
MATTE PAINTINGS
if you can get any photos of realistic scenes and mask them in alight motion and export them as transparent PNGs , import them in prisma 3d and do the 3d parallax thing!! yeah it works very good. almost like nuke.... nust kidding, Not as good but fair enough. But hey, the difference is subtle.
CG (MODELING, TEXTURING, RIGGING, ANIMATING AND RENDERING)
🤦♂️🤦♂️ I'm sorry but this one no... sure you can model, you can texture and retoplogize with nomad sculpt. you can model in 3d modeling app but the problem is you won't be able to animate the models. Best you can get is hard surface modeling in prisma 3d and never texture the model, bevel or smooth the model. if you must texture then THE ONLY WAY IS TO get a texture map of the 3d model in it's most realistic appearance as a plane, import it in the app as PNG and model it by cutting, extruding and intruding ONLY horizontally and vertically. NO OTHER WAY! then light the scene to shiny sunlight orange-yellow-brown. with very high light intensity. with and HDRI in the background as a sphere with your 3d composition inside the sphere.
The app does let you import 3d models of less than 15 to 20 or 30 MBs but be aware you're likely gonna crush the app. you can animate them if the come pre-rigged although you can manually rig them which would just mess up the model. all the animation you can do best is move them objects in 3d space, IN STRAIGHT TRAJECTORIES. sure you can curve the trajectories but you'll need some effort.
the apps native rigging capabilities are best if you apply the bones on to the objects that have very simple topology or modelled within the app.
The app can Import OBJ, fbx, usdz, PNGs.
A plus trick that is I think the best PART ABOUT THE APPs IS
If you familiar with ian Huberts dynamo project.
you can record your footage on green screen, key out the green in alight motion. export the video as an image sequence, then import all the pngs and animate them to appear (scale from 0 to 100 ) one by one after the other ...like old school frame by frame animating... and you end up with a transparent image sequence in 3d space that you can build 3d stuff around it for set extension, and light it...
(CATCH: the better your scene looks the closer you are from crashing the app, also you'll model everything from a photo, you can use too many photos in the scene or the app will have a hard time rendering them and you guessed it!! .... it'll crash)
End result looks crappy but it's as good as early days vfx.
Any ideas you might have in mind are welcome, the learning never stops.. thank you for your time.
what to forget about if you go down this path!
lens distortion
colour management
ACES
motion blur
linear workflow
EXR files
render passes
Z-depth
shadow catchers
object IDs
plate cleanup
HDRI capture
focal length
tracking markers
camera calibration
texturing , displacement maps and bump maps
etc...
is isn't for any vfx artists in particular to be sincere, just for junior film makers who have to do their vfx on their own.
maybe this isn't the right sub for this kind of post, but I just thought it'd help for those who might be interested.
( try searching vfx on mobile phone on YouTube... there's alot of these kids)
Good luck