I have 4 different eyeshadow bases that I use pretty much everyday (or whenever I need to apply eyeshadow). They make the shadow last all day (no kidding!), prevents creasing and they also bring out the true colour of the shadows.
I ♥ them!
Urban Decay Primer Potion (£11.50) - I'm sure you all know this, it's kind of famous! This nude, silicone filled potion dries instantly on your lids and helps create the most beautiful finish to your look. I only use a tiny amount on each lid, rub it in well, and voila - I'm ready for any eyeshadow! Makes my MAC shadows last aaaaaaaall day.
Too Faced Shadow Insurance (£13)- This little blue baby is Urban Decay's fiercest competition on the primer market. People either prefer the PP or the Shadow Insurance. It is more liquidy, but gives the same result (in my opinion). I usually just squeeze a bit out on my finger and gently pat it on my lids. It has no colour, is also silicon based and it evens out the skintone on your eye lids - perfect!
Too Faced Lock Down in Bondage (£13) - This creaseless cream eye shadow has been infused with shadow insurance primer and can be used on its own or just as a base. The colour of the one I own is a very light brown with gorgeous metallic glitter. I sometimes use this as a shadow when I'm being lazy, but usually I put a powder shadow over it. It's as good as the Shadow Insurance, which means it's a better deal, as this is really two products in one little cute bottle!
MAC Paint Pot in Bare Study (£13)- A lot of people prefer to use MAC's paint pots as eyeshadow primers (Allthatglitters21 from youtube for instance). Occasionally I will use Bare Study as a primer, but for some reason I struggle to apply this evenly. I use my finger as I only want a light layer (to avoid any creasing), but I always manage to smudge it in places where I don't want it! It is a gorgeous colour though, Bare Study... it's a soft shimmery beige with gold pearl. I prefer it as a colour on it's own actually, it is too pretty to cover up.
In conclusion, I think I prefer the Urban Decay Primer Potion out of the above 4 primers. I seem to reach for that one the most. It's the easiest to apply and gives a 100% flawless result.
What kind of eyeshadow primer do you use?