These iOS and Android apps:

PubMed Hub (Android): https://play.google.com/store/apps/details?id=com.pubmedhub&hl=en_US

PubMed Hub (iOS):

https://itunes.apple.com/us/app/pubmed-hub/id1222331895?mt=8

Genes & Diseases (Android):

https://play.google.com/store/apps/details?id=com.GnD&hl=en_US

Genes & Diseases (iOS):

https://itunes.apple.com/us/app/genes-diseases/id1440373182

Journal IF (Android):

https://play.google.com/store/apps/details?id=com.journalif&hl=en_US

Journal IF (iOS):

https://itunes.apple.com/us/app/journal-if/id1446598571

Health Topics (Android):

https://play.google.com/store/apps/details?id=com.healthtopics&hl=en_US

Health Topics (iOS):

https://itunes.apple.com/us/app/health-topics-nih/id1444538300

CrossRef (Android):

https://play.google.com/store/apps/details?id=com.crossrefhub&hl=en_US

CrossRef (iOS):

https://itunes.apple.com/us/app/crossref-hub/id1430866797