There is nothing wrong with ApeX. It settles through StarkEx, the same validity-proof infrastructure that secured dYdX v3, charges roughly 0.02% maker and 0.05% taker, supports a broad market list, and has never been exploited. In most categories that would make it a strong recommendation.
Why depth decides this category
Derivatives liquidity is reflexive. Traders go where fills are good, market makers go where traders are, and the gap between the leading venue and the fifth compounds. ApeX's books on BTC and ETH are usable for retail size; beyond that, slippage on a moderate order will exceed any fee advantage the venue offers. The fee schedule is a marketing lever when liquidity is the binding constraint.
Architecture
StarkEx settlement means trades are proven and settled on Ethereum, with custody enforced by validity proofs rather than trust in the operator. Order matching is off-chain. Users can force-withdraw through the settlement layer if the operator stops serving them, which is the meaningful protection this architecture provides.
Risk profile
No exploit history, audits in place, and an insurance fund. The notable structural point is sponsorship: ApeX's development and liquidity support have been closely tied to a single backer in the Bybit ecosystem, which concentrates the risk that support is withdrawn or redirected.
Who should use ApeX
Traders already in its ecosystem, or those wanting a second venue for specific markets where its book happens to be adequate. For primary derivatives trading, Hyperliquid, dYdX and the larger centralised venues all offer materially better execution.