Glo Nigeria offers a variety of internet data plans you can subscribe to using your Android smartphone or j2ME phone. The bundles are categorized based on their validity periods which means their expiry time length. There are plans for 24 hours (1 day), plans for 7 days (1 week), and plans for 30 days (1 month). See the tablescription plan that best suit your needs.
'Validity' means how long the subscription will last.

'SMS to 127' describes the code you would send to 127 to activate the plan.
'USSD Code' is the alternative method to activate the plan by dialing a code.

Update (Feb 14 2016): Glo increases data capacity of monthly plans. The 'Always Micro' data plan has been increased to 1.2GB for N1000. other affected plans include My Phone, So Special, Always Min and Always Max which were all increased to match the change.

Get the subscription code at http://akinbabatunde.com/glo-data-bundles/