Hello !
Ive watched a couple mobile courses and some landers from the teacher has picture of 15kb.. isnt it too large ?
Whats the size of a banner and lander I should shoot for size wise ?
Thanks !
15 KB is fine.
Remember that on 3G you can do 100's of KB per second depending on carrier/location, and even 500+ on 4G.
Banners should be as light as possible without compromising quality too much. For 320x50 I'd stay under 30 KB. For 300x250 I'd try to stay under about 40-50 KB. I haven't split tested file sizes but on today's smartphones a 50 KB 300x500 image isn't very difficult to download.
Landers... just as light as possible. Landers are easier to split test so try a cut down 20 KB lander vs a 100 KB one. Load speed matters but we can't tell you any optimal size because there isn't one. Just don't make it 10 MB.