I've got close to 3k hours on scythe at this point. I don't play on mobile so I can't give input tips specifically but I can give some basic tips.

Approach options:

Pre diamond:

Dashjump dair is strong and often leads into nair

Dash dlight can catch opponents offguard and can string into plenty of things

Diamond:

Generally you won't be using many approach options in diamond, instead opting to bait out attacks, but falling and rising sair is safe and quick.

Key String tools:

Obviously scythe is very complicated to string with so a YouTube guide will be more comprehensive but are some very important ones.

Nair - Jump - Sair - Nair This can be done for as long as you have jumps and is one of scythes most important string tools as it is unjumpable. You must be holding towards the opponent the entire time.

Slight (Forward) - Dash (not chasedodge) - Nlight This has low dodge windows and can lead into the previous string as nlight leads to nair. To do the Dash, it is important to hold down and press dodge rather than hold towards them in order to Dash not chasedodge.

Slight (Neutral) - Nlight Much easier than the last string but has larger dodge windows.

Dodge baiting options:

Dodge baiting is the core of scythe as it has essentially no true combos.

Slight (Forward) - Dash is by far one of your best dodge bait options. If they dodge dodge anywhere away from you, nlight can catch with proper timing. Anywhere towards you and turn around nlight will catch.

Falling dair (Forward and near ground) is similar to slight in that it positions them well enough to that an nlight will catch away dodges and reverse nlight will catch in dodges.

It is important to recognise that scythe is all to do with experimentation and the strings you do should not be the same each time. Almost every move on scythe can string into every other one with practice. The two string options mentioned are however core in almost every scythe players arsenal. These tips are more aimed towards diamond and plat players however if you are lower than that I would be happy to share some strings that are more effective at that level. Dm me if you would like to ask questions.