This thread on CBR has a weekly breakdown of what's being released.
http://community.comicbookresources.com/showthread.php?30672-Secret-Wars-Checklist
Latest update was on May 2, here's the current list:
SECRET WARS WEEKLY RELEASE DATES (Updated May 2nd 2015)
LD = Last Days
BW = Battleworld
WZ = Warzones
29/04/15 - New Avengers #33, Avengers #44
02/05/15 - Secret Wars #0, All New All Different Avengers #0 (Post Secret Wars)
03/05/15 - Armour Wars #1/2 (Exclusively at ToysRUs)
06/05/15 - Secret Wars #1, Secret Wars Prelude TPB
13/05/15 - Secret Wars #2, Captain America and the Mighty Avengers #8 (LD), Magneto #18 (LD)
20/05/15 - A-Force #1 (WZ), Deadpool's Secret Secret Wars #1 (WZ), Loki: Agent of Asgard #14 (LD), Master of Kung Fu #1 (BW), Planet Hulk #1 (WZ), Secret Wars: Battleworld #1 (BW), Spider-Verse #1 (WZ), Ultimate End #1 (BW)
27/05/15 - Inferno #1 (WZ), Inhumans: Attilan Rising #1 (BW), MODOK: Assassin #1 (WZ), Old Man Logan #1 (WZ), Secret Wars 2099 #1 (WZ), Secret Wars Journal #1 (BW), Infinity Gauntlet #1 (WZ), Where Monsters Dwell #1 (WZ)
03/06/15 - Secret Wars #3, 1602: Witch Hunter Angela #1 (WZ), Amazing Spider-Man: Renew Your Vows #1 (WZ), Armour Wars #1 (WZ), Future Imperfect #1 (WZ), Giant Size Little Marvel AVX #1 (WZ), Master of Kung Fu #2 (BW), Secret Wars: Battleworld #2 (BW), X-hinction Agenda #1 (WZ), Years of Future Past #1 (WZ)
10/06/15 - Captain America and the Mighty Avengers #9 (LD), Captain Marvel and the Carol Corps #1 (WZ), Ghost Racers #1 (BW), Inferno #2 (WZ), Inhumans: Attilan Rising #2 (BW), MODOK: Assassin #2 (WZ), Marvel Zombies #1 (BW), Mrs Deadpool and the Howling Commandos #1 (WZ), Old Man Logan #2 (WZ), Secret Wars 2099 #2 (WZ), Secret Wars Journal #2 (BW), Silver Surfer #13 (LD), Spider Verse #2 (WZ), Squadron Sinister #1 (WZ), Thors #1 (BW), Ultimate End #2 (BW), Weirdworld #1 (WZ)
17/06/15 - Secret Wars #4, A-Force #2 (WZ), Amazing Spider-Man: Renew Your Vows #2 (WZ), Armour Wars #2 (WZ), Deadpool's Secret Secret Wars #2 (WZ), Future Imperfect #2 (WZ), Guardians of Knowhere #1 (WZ), Magneto #19 (LD), Ms Marvel #16 (LD), Runaways #1 (BW), Infinity Gauntlet #2 (WZ)
24/06/15 - Age of Ultron vs Marvel Zombies #1 (BW), Black Widow #19 (LD), E is For Exhinction #1 (WZ), Korvac Saga #1 (BW), Loki: Agent of Asgard #15 (LD), Planet Hulk #2 (WZ), Star Lord and Kitty Pryde #1 (BW), The Punisher #19 (LD), Weirdworld #2 (WZ), Where Monsters Dwell #2 (WZ), X-Men '92 #1 (WZ)
01/07/15 - Secret Wars #5, Amazing Spider-Man: Renew Your Vows #3 (WZ), Future Imperfect #3 (WZ), Giant Size Little Marvel AVX #2 (WZ), Hail HYDRA #1 (WZ), Inhumans: Attilan Rising #3 (BW), Master of Kung Fu #3 (BW), Red Skull #1 (BW), Secret Wars Journal #3 (BW), Squadron Sinister #2 (WZ), Ultimate End #3 (BW), X-tinction Agenda #2 (WZ), Years of Future Past #3 (WZ)
08/07/15 - 1872 #1 (WZ), Age of Apocalypse #1 (WZ), Civil War #1 (WZ), Ghost Racers #2 (BW), Inferno #3 (WZ), Marvel Zombies #2 (BW), Mrs Deadpool and the Howling Commandos #2 (WZ), Mrs Marvel #17 (LD), Old Man Logan #3 (WZ), Runaways #2 (BW), Secret Wars 2099 #3 (WZ) Siege #1 (BW), Spider Island #1 (WZ), Spider Verse #3 (WZ), Weirdworld #3 (WZ)
15/07/15 - Armour Wars #3 (WZ), Captain Britain and the Mighty Defenders #1 (WZ), Captain Marvel and the Carol Corps #2 (WZ), Guardians of Knowhere #2 (WZ), Korvac Saga #2 (BW), Magneto #20 (LD), Planet Hulk #3 (WZ), Secret Wars: Battleworld #3 (BW), Silver Surfer #14 (LD), Infinity Gauntlet #3 (WZ), Thors #2 (BW), Where Monsters Dwell #3 (WZ)
22/07/15 - A-Force #3 (WZ), Civil War #2 (WZ), E Is For Extinction #2 (WZ), Loki: Agent of Asgard #16 (LD), Star Lord and Kitty Pryde #2 (BW), The Punisher #20 (LD)
29/07/15 - 1602: Witch Hunter Angela #2 (WZ), Age of Apocalypse #2 (WZ), Age of Ultron vs Marvel Zombies #2 (BW), Black Widow #20 (LD), Deadpool's Secret Secret Wars #3 (WZ), Hail HYDRA #2 (WZ), MODOK: Assassin #3 (WZ), Spider Island #2 (WZ), X-Men '92 #2 (WZ)
August - 1872 #2? (WZ) House of M #1? (WZ)
NOTE: X-Men '92 will be released one month early digitally. 1872 was delayed from June to July and House of M appears to be delayed to sometime in August.