I design in Photoshop at whatever resolution is the most common of our users, and I also preview my designs on that most common device (typically iPhone 6, Nexus 5). When designing, I keep in mind the divisions or multiplications to asset size when scaling up or down to additional resolutions (@1x, @3x), (mdpi, hdpi, xxhdpi). I do not always work pixel-perfectly, because that wastes time, plus some assets or text areas or whatever sometimes have larger bounding boxes than how I've laid them out (for whitespace/dimension scaling purposes) so I find tools like Zeplin don't work well for me.
What I end up doing is manually marking up dimensions (usually margin/padding are depicted with semi-transparent coloured bars, with the colours working as a legend to quickly see which dimensions are shared, which helps with defining constants. I try to keep these consistent between screens, too). Then, larger rectangles for image assets/text fields/whatever to help show where whitespace is included in the asset, marked up with any size constants, font sizes, file names, etc.
All dimensions in pt/dp or %. I've had a lot of success with handing this off to developers and only needing minimal tweaking afterwards.
I design in Photoshop at whatever resolution is the most common of our users, and I also preview my designs on that most common device (typically iPhone 6, Nexus 5). When designing, I keep in mind the divisions or multiplications to asset size when scaling up or down to additional resolutions (@1x, @3x), (mdpi, hdpi, xxhdpi). I do not always work pixel-perfectly, because that wastes time, plus some assets or text areas or whatever sometimes have larger bounding boxes than how I've laid them out (for whitespace/dimension scaling purposes) so I find tools like Zeplin don't work well for me.
What I end up doing is manually marking up dimensions (usually margin/padding are depicted with semi-transparent coloured bars, with the colours working as a legend to quickly see which dimensions are shared, which helps with defining constants. I try to keep these consistent between screens, too). Then, larger rectangles for image assets/text fields/whatever to help show where whitespace is included in the asset, marked up with any size constants, font sizes, file names, etc.
All dimensions in pt/dp or %. I've had a lot of success with handing this off to developers and only needing minimal tweaking afterwards.