В каком криптоприложении нет комиссий за транзакции?

There’s no app that’s permanently fee-free; some run zero-fee promos, and quote-based services like ChangeNOW show all costs inside the rate (no extra trading commission). Other zero fee platforms earn from spread the spread between buy and sell orders.

На какой криптобирже самые низкие комиссии?

At entry-tier spot, MEXC is often lowest (≈ 0% maker / 0.05% taker), but your effective fee depends on volume tiers, token discounts, and spreads; ChangeNOW is competitive for quick, transparent swaps.