Rhalgaln's page

UMD is needed to activate a wand unless the user has that spell on his/her class list.

So, if your familiar wants to use a wand, and doesn't have the spell on it's class list then it needs to use UMD.

I don't think a familiar can have class levels, so unless it has some kind of spell casting, like a dragon or an Illend, (I don't know of any familiar that can cast) it must use UMD to activate any wand.

Hmm, sadly seems you're right with that.

So a fire mephit is able to cast a scorching ray as spell like ability
can he use a wand of scorching ray?
But since he does not have a spell list, are spell like abilities counting against that rule?

This leads to the next question:
Although a familiar uses skills on masters or own level whichever is higher you can use this skill only trained. So does the familiar need to have at least a single rank in UMD to use ist at all (with the higher rank of master or own skill) ?

Skills: For each skill in which either the master or the familiar has ranks, use either the normal skill ranks for an animal of that type or the master's skill ranks, whichever is better. In either case, the familiar uses its own ability modifiers.

Clear as a bright crystal 'till here:

Regardless of a familiar's total skill modifiers, some skills may remain beyond the familiar's ability to use.

Which skills remain beyond a familiars ability to use and which remain beyond an improved familiars ability to use and why?

=> discuss that with your GM, before deciding which feat to buy.

Improved Familiar is a useless or quite powerful feat which definately needs much more attention.

@ Stéphane Le Roux

The only unclear thing, in RAI, is whether an improved familiar use the list of class skills of other familiars or another list (by RAW it's clear: class skills are Acrobatics, Climb, Fly, Perception, Stealth, and Swim; incidentally, by RAW, your mephit doesn't have Bluff +8, only Bluff +5 - 3 ranks +2 Cha).

As the Rules say:

Improved familiars otherwise use the rules for regular familiars, with two exceptions: if the creature’s type is something other than animal, its type does not change and improved familiars do not gain the ability to speak with other creatures of their kind (although many of them already have the ability to communicate).

So the type of a mephit continues to be "outsider" with class Skills and feats (dodge, improved initiative) of outsiders.
As there are only two named exeptions the standard familiar class skills add to the list of outsider class skills.

On my opinion nothing is really clear with regard to improved familiars.

@Peter:
A familiar does not level up, as it does not use Monster advancement. Instead it uses the feats, AC increase and Int from the familiar Table.

It uses the skill levels from his Master with the Bonus from the referring stats of the Improved Familiar.
It's BAB is the one of the Master.

You have to discuss with your GM if "effects based on HD" is only incoming effects or if for example the Breath Weapon DC are adjusted by Masters Level.
Same Problem for Spell like abilities.

Use magical device is only needed to use unidentified magical things. So your Mephit can use any of your identified wands without a test if you tell him the activation word.