The government has promised a free and fair vote, and has dismissed charges of abuses in previous votes.
“The elections have generally been peaceful, far more peaceful than anticipated,” Seidu Alidu, an analyst.
Congo official flags budget worries over already delayed election
A new president brings the promise of an end to repression and freeing up development aid, frozen because of human rights concerns.
Opposition candidate Jean Ping had alleged fraud and appealed against Bongo's victory in the August election.
The DRC is shellshocked after a peaceful protest turned deadly, yet its president remains invisible.
An African political lesson from Uganda: Don’t insist an election was rigged, or hold your own swearing in
Museveni and Besigye are caught in a death dance that can go badly for Uganda, and illustrates the end game for Africa's revolutionary parties
Besigye has said his detention was designed to block him from gathering evidence of fraud in what he called a "scandalous" election
The strategically located port nation enjoys solid growth of six percent a year, but unemployment is high at 60%, and almost 25% live in poverty
October vote modified the constitution, removing a 70-year age limit and two-term barrier to enable him to extend his rule
Even Museveni critics offer grudging admiration. "He's not smart, he's extremely smart." Doing others' dirty work abroad has won him a free pass.
UPDATE: Uganda’s Museveni declared winner of chaotic election, as detained rival Besigye rejects result
“Ugandan authorities created an atmosphere of intimidation in the run up to and during Thursday’s vote”
The country has had more than 20 coups or attempts at seizing power since it gained independence from France in 1975
UPDATED: US tells citizens to stay indoors, as Museveni challenger Besigye arrested after troubled Uganda polls
The arrest - the third for the opposition politician in a weeks - seem to be part of a bid to stop the opposition from releasing their results tally
UPDATED: Long-term ruler Museveni in early lead, as voting enters second day in chaotic Uganda election
Because it was the opposition stronghold affected, some see sabotage rather than incompetence in the election day chaos
Besigye was later released and driven to his home in a police car. He described his arrest as "intimidation"
'Confusing' electoral college, running battles: Five ways in which a US election is not like its African peer
Since the 1960s, nearly two-thirds of African elections have resulted in victory for the incumbent, though there have been some notable defeats too
Birthplace wars and conspiracy theories: Five ways in which US presidential race is like an African election
When South African comedian Trevor Noah joked that Donald Trump might be America’s first "African" president, he might have been on to something
Instability and conflicts to watch in 2016 - and why this AU election should matter the most to them
Major changes happening at the African Union that will define and affect the continents path in times ahead