Following the spiral on Internet banking in most nigerian banks, the safest means of downloading respective banks app is through their official website.
Kindly be guided about suspicious mail supposedly from your bank asking you to click any link requesting to input your banking details. This is ember month and fraudster are on rampage looking for gullible victims to food on.
Please be wise...

Access Bank Plc
Plot 999c  Danmole Street, Off Adeola Odeku/Idejo. Street,
 Victoria Island, Lagos.
www.accessbankplc.com

 Citibank
11, Idowu  Taylor Street,
Victoria Island, Lagos.
www.citigroup.com

 Diamond Bank Limited
2, Ajose  Adeogun Street,
Victoria Island, Lagos.
www.diamondbank.com

 Ecobank Plc
www.ecobank.com

 Entreprise Bank
Plot 143, Ahmadu Bello Way,
Victoria Island, Lagos

 First Bank of Nigeria
36, Marina, Lagos.
www.firstbanknigeria.com

 First City Monument Bank Plc
Primrose Towers, 17A,
Tinubu Street,Lagos.
www.fcmb-ltd.com


 Guaranty Trust Bank
Plot 1669, Oyin Jolayemi Street,
Victoria Island, Lagos.
www.gtbplc.com

 Keystone Bank
Plot 707, Adeola Hopewell Street,
Victoria Island, Lagos.
www.platinumhabibbank.com

  Mainstreet Bank
94, Broad Street, Lagos
www.afribank.net

 Stanbic-IBTC Bank Plc
Walter Carrington Crescent,
Vicoria Island Lagos
www.stanbicibtc.com

  Skye Bank Plc.
www.skyebank.com

 Standard Chartered Bank Nigeria Ltd
105B Ajose Adeogun street,
Victoria Island, Lagos.
www.ng.standardchartered.com

  Sterling Bank Plc
20, Marina, Lagos.
www.sterlingbankng.com

  Union Bank of Nigeria Plc
36, Marina, Lagos.
www.unionbankng.com

  United Bank for Africa Plc
UBA House, 57, Marina, Lagos.
www.ubagroup.com

  Unity Bank Plc
Plot 785, Herbert Macauly Way, Central Business District, Abuja.
www.unitybankng.com

  Wema Bank Plc
Wema Towers, 54, Marina, Lagos.
www.wemabank.com

   Zenith Bank Ltd
Plot 84, Ajose Adeogun Street, Victoria Island, Lagos.
www.zenithbank.com

http://e-banking9ja..com/2015/11/safest-channel-to-download-internet-app.html