Avatrade is a well regulated fixed spread European Forex broker. They offer 0.9 pips spread for EUR/USD, and their spread is generally quite low for most instruments. But Avatrade does not have a local office in Nigeria.
Alpari is one of the oldest broker in the world & also one of the largest in terms of monthly trading volume.
Exness is #5 in our recommended forex broker list for Nigerian traders. Exness Group is a regulated broker in UK & EU.
IC Markets is an ASIC regulated ECN type broker that offers very Forex trading at very competitive fees.