So, splicing applies when sending _(splicing-out)_ or receiving _(splicing-in)_ on-chain?

Does splicing-in also apply to LN transactions greater than my channel's current capacity?

And finally, regarding the 'max-fee amount' in the Channel Management tab (iOS), is that the max-fee in sats I'm willing to pay to splice?

Anonomoto

The channel you opened will only reduce in capacity if you send from it to BTC address ( = on-chain = splicing out).

The general idea is great, when you do it, you'll have almost 4m sats of inbound liquidity available with no fees

bitcoin

Phoenix Wallet clarity

The channel you opened will only reduce in capacity if you send from it to BTC address ( = on-chain = splicing out). 
The general idea is great, when you do it, you'll have almost 4m sats of inbound liquidity available with no fees