The Gas Limit is calculated automatically in Coinomi.
Think of using a car analogy: You need to drive 500km, and you need 30 litres of gas to get there. Ideally, in the most efficient scenario, your car tank's capacity will be 30 liters, and all of the gas will be consumed excactly as you reach your destination. In ETH, those are called gasLimit (tank capacity) and gasUsed (actual gas used by tx). v
Manually setting the limit to 200000 for a transaction that really requires for eg. 68000 is like having a 100 litre gas tank but only fill the 30 needed for your trip, in the analogy above. In Ethereum this is even more inefficient because the excess gas would have to be returned to your ETH address which might leave dust remainders in your wallets.
This is what happens in Coinomi: upon constructing your transaction, Coinomi asks the Ethereum network about the precise limit your transaction needs, and sets that as the limit automatically, ensuring ideal consumption without need for returns.
In short, in Coinomi, always, gasUsed = gasLimit.
Therefore, you do not need to worry about gas limits when participating in ICOs or when sending ETH or tokens to contract addresses. The work will be done behind the scenes and the ideal, correct limit will always be set. The transaction will need and spend that excact amount.
Concerning ETH Fees/Gas price:
ETH fees are completely different than BTC ones: The fee you see in our .../Settings/Transction fees page, is the ETH price of one (1) gas. A normal ETH transaction requires 21000 gas. Smart contracts, tokens etc might require more as they contain complex opcodes that require random amounts of gas.
The amount of ETH in the transaction does not matter in Ethereum, unlike BTC, and it does not affect the fee.
The default price of 1 gas in Coinomi is currently at 0.00000002 ETH (20 "Gwei") so a normal send transaction will cost approximately 0.00042000 ETH.
There are two scenarios where higher gas price can be advantageous, but it has nothing to do with the gasLimit.
1. The very beginning of ICOs, where everyone tries to get tokens and the first blocks fill up fast.
2. Later on in the life of some tokens, when they gain mass traction and following and have many transactions.
Manually raising the price of gas might present better chances of inclusion on blocks in either case.
Please do not increase the fee dramatically, try changing it to 0.00000004 or 0.00000006. Higher fees will result in extremely high total fees in ETH.
You can also consult: https://etherscan.io/chart/gasprice