Since Bonded Item is treated like Arcane Bond, can I spontaneously cast one of my known spells each day in addition to the bonus item-based spell granted in the description? Or does the latter replace the former?
Also, the archetype says I can't teach my bonded item spells from another bonded item, but seems to make no such restriction for witch's familiars. Can I teach it spells from a witch's familiar or not? Can a witch's familiar learn spells from my bonded item?
The bonded witch alludes to this, but while you still technically have the ability to cast spells from your spellbook, it doesn’t work because you don’t have a spellbook.
Since a bonded witch does not have a spellbook, starting at 2nd level, a bonded witch’s bonded item can be used once per day to cast a spell dependent on the type of bonded object chosen by the bonded witch.
I’m not sure what to think about learning from familiars. The text basically says you can, but that could just be an oversight.
I don't see anywhere where the text says you can learn a spell from a witch's familiar.
You don't have the witch familiar class feature, which is where most witches get that ability from. The bonded item doesn't say that you can (the calirify text of not learning from another bonded item doesn't in any way grant the ability to learn from a familiar anymore than it grants the ability to learn from an alchemist formula book.)
Similarly, Witch's familiar don't have any ability to learn from your bonded item.
A bonded witch starts with the same number of spells and gains new spells the same way as a witch, and can even add spells by learning them from scrolls in the same way, but a bonded witch cannot learn spells from another bonded item.
That would include learning spells from another witch's familiar.
I am pretty sure that 'gains new spells the same way as a witch' refers to 'Spells Gained at a New Level.' this is especially clear when the next phrase 'and can even add' is looked at.
You gain what you gain as you level, and you can add (via scrolls). the 'gained' and 'add' are viewed as two separate things.
In any event, even if the bonded witch gained the ability 'Familiar Teaching Familiar' it wouldn't do them any good, as they don't have a familiar that can learn from another familiar.
The way "And can even" is worded sounds more like clarifying words than additive words to me. This would be backed up by the fact that they specify that the bonded item cannot learn from other bonded items. They wouldn't need to specify that if the rules for learning from other familiars wouldn't otherwise still be in play.
Hence my confusion, and need for clarity. :P
Can a bonded witches' wand being used as a toy by another witches' cat pick up new spells? I'd hope so, it makes no sense to cut them off from a source of learning spells which non-bonded witches have without mentioning it specifically. And the new toothmarks have to be good for something.
Concerning learning from a familiar, reading everything, I would say no.
Bonded Item (Sp) is a replacement of the Witch's Familiar class feature, not an alteration of like say the Champion of the Faith Warpriest's Sacred Weapon (Su), or the Weretouched Shifter's Lycanthropic Empathy (Ex).
As it is a replacement, none of the base rules from Witch's Familiar can be applied. This is likely why it is mentioned the Bonded Item can learn spells from scrolls, something in base Witch's Familiar that needs to be mentioned now as part of the new replacement ability.
As for the spontaneous casting, as the Witch has no spellbook, also no. This is pounted out in the feature.
Since a bonded witch does not have a spellbook, starting at 2nd level, a bonded witch’s bonded item can be used once per day to cast a spell dependent on the type of bonded object chosen by the bonded witch.
Even if you consider 'and can even' to simply be clarifying words that were unnecessary because of the previous sentence, there is nothing that gives it the ability to learn spells from another familiar. A bonded item doesn't have the ability to commune with a familiar as just one problem.
In the witche's familiar section it talks about 3 ways that you add spells to a familiar. They are called:
1) Spells Gained at a New Level
2) Familiar Teaching Familiar
3) Learn from a Scroll
To me it is obvious that the bonded witch keeps item 1, and item 3, but it doesn't get item 2. It doesn't even get a substitute of item 2 where bonded item teaches bonded item.
A difference I'm seeing between the two is that the normal witch familiar talks about the familiar learning spells and that it's the familiar learning from the other familiar. The Bonded witch talks about the witch learning spells and how the witch can not learn spells from another bonded object. This results in following redundant statement.
The bonded item stores all of the spells that the bonded witch knows, and the bonded witch cannot prepare spells that are not stored within it.
It's basically stating that the witch can't prepare spells they don't know.
for the OP's 1st question, I agree with Isaac that It specifies what spells can be cast spontaneously based on the type of item it is. I think it's worth noting that there is no indication that you have to know the spell (since it's not being prepared), so this could grant access to spells the witch might not normally get.
As for the second question, Since the bonded item is a bonded item and not a familiar it's no longer eligible for one familiar learning from another familiar. It's also called out that a witch can not learn a spell from another witch's bonded item. So, two bonded witches are unable to exchange spells.
I guess the justification for this is that if a witch loses their bonded item it can be replaced for 200gp per level (instead of 500) and they retain any extra spells that were added via scrolls. IMO this is still terrible since it takes a week to replace a bonded item, not 24 hours. Leaving you without spells for a substantial amount of time.